LSU Libraries - Searching Techniques and Strategies Tutorial

In this tutorial, you will learn how to select a topic for a research project, and generate search terms that you can use to do online searching for information about that topic. You will learn about concepts like truncation and boolean logic, which will help you use those terms to formulate more complicated and precise searches, which will save you time and effort. These searching techniques are very general, and will work in a wide variety of online databases like the Online Catalog, Academic Search Premier, or Internet search engines.

This is a text-only printer-friendly version of the Online Catalog - Advanced Searching Tutorial. It does not include picture examples provided in the primary version of this tutorial.

Generating Search Terms

The process of picking out a topic and defining terms for any kind of research project is a lot like planning a trip: if you don't know where you want to get to, then you can't plan how to get there. Formulating a definite topic at the outset of your project ensures that you don't waste any time running after information that you don't want or can't use, and makes the entire research process easier on you.

The first step is to identify your topic. You can do this first in general terms. Look at your interests and hobbies. Is there anything there you could make a research project out of? The more interested you are in your topic, the more energy you'll invest in it. Do you follow sports? Do you like computers? Maybe you read a lot of fantasy and science fiction? All of those are interests you can incorporate into a research project.

Once you have a general topic, you need to start refining it, make it more definite. For instance, you can't just do a research project (at least, not a good one) on "computers." There's way too much information about computers out there.

There's information on the technical aspects of computers-how they're put together, what they're made of, what kinds of software they run.
There's information on the social aspects of computers-how computer technology has changed the lives of people and the society we live in.
There's information on the financial aspects of computers: the computer industry, the people who run and own computer companies, how much computers cost and how many people are buying them.

Say we wanted to do a project on pollution. There are all kinds of aspects of pollution, but we decide we want to focus on the effects of pollution on the environment. That's better, but it's still not specific enough. What kinds of pollution? There's everything from smog to oil spills to the depletion of the ozone layer. And what part of the environment? The world is a pretty big place. We need specific things to look up, specific kinds of pollution and specific effects on the environment. "The Depletion of the Ozone Layer and Its Relationship to the Increase in the Rate of Skin Cancer" is perfect. You need to try to make your topic as specific as possible. Here are some more examples:

Too broad

Gender in Literature
Pollution and the Environment
Politics and the Media
Violence on Television

More specific

The Depiction of Women in Old English Epics
The Effects of Oil Spills on Wildlife
The Presentation of Monica Lewinski in the Media
Jerry Springer and the Culture of Violence

Encyclopedias can be of great help here if you don't know much about your topic. You can also try talking to people knowledgeable about your topic and asking them for suggestions

Now that you know your subject, you need to determine what subject area it falls into.

Humanities: This generally includes anything dealing with literature, art, history, archaeology, folklore, languages, music, philosophy, religion, architecture, and theater. An example of a humanities topic would be "Standards of Gender in Old English Epics" or "Logical Proofs in Philosophy since Descartes."
Social Sciences: This area deals with any topics concerning social work, anthropology, law, business, psychology, education, political science, sociology, mass communication, or gender studies. "The Roman Arena: Jerry Springer and the Culture of Violence" or "The Depiction of Monica Lewinsky in the Media" are social sciences topics.
Sciences: This relates mostly to the "pure" sciences, such as chemistry, physics, biology, geology, mathematics, and astronomy, but also includes botany, environmental science, nutrition, oceanography, and medicine. "Heartworm Prevention in Milk Cows" or "Did Comets Kill the Dinosaurs?" are science topics.
Applied Sciences: This includes anything relating to engineering or technology. "The Pentium Chip: the Future of Computer Technology" or "A Comparison of the Tensile Strength of Metals Used in Skyscrapers" are applied sciences topics.

Since many (not all) periodical databases tend to be divided by subject area, it's important to know where your topic fits in so that you can select an appropriate database and find magazine articles you can use.

Now you are ready to generate search terms. Get a sheet of paper and a thesaurus. Write your topic at the top of the page. Now list the important words or phrases in your topic. For instance, our topic on skin cancer and the ozone layer might break down into:

Skin
Cancer
Ozone Layer
Relationship
Increase

These are your keywords or search terms.

Now, open the thesaurus and look up your search terms. Find as many alternate words for your search terms as you can, and write them down. For instance, let's say our topic was "The Effects of Oil Spills on Wildlife." Our list might look like this:

Oil
Petroleum

spill
Pollution
Waste

Wildlife
Animals
Birds
Seals
Seagulls
Fauna

In this case, you might also list the names of specific oil spills, such as the Exxon Valdez or the Prince William Sound. The more terms you have to search with, the more information you'll be able to find. It also gives you a "spare tire": if one group of search terms doesn't seem to bring anything up, you can switch to another.

Okay, so now you have a topic, and a list of search terms. How can you use them?

For the rest of this module, we'll be looking at how to use those terms to construct searches that you can use on Internet search engines or periodical indexes to find web pages or periodical articles that you can use for your project. If you need help with selecting and using periodical indexes, please see the Periodical Information module.

All the concepts we will be discussing will be very general, and almost all are usable in just about any electronic resource you choose to use. If you need help with a specific database, look for it's help files. They all offer help or searching hints and tips which can greatly improve your search results.

Boolean Searching

The results of a simple keyword search can be overwhelming. In a keyword search, the computer will look at all the records in the catalog and bring back all the ones that contain the word or phrase that you specify anywhere in the record. This is very important! If you type in the word "guns," you are not only going to get information on hand guns, but information about electron guns, a book titled Guns or Butter about Lyndon Johnson, books by Walter Guns, and any other item that has the word "guns" somewhere in its record. Your results list can be very long. It's for just that reason that we have what are called Boolean Operators, special words that have specific meanings within the context of a search and allow you to link terms together to make your searches more specific. The Boolean terms are one of the most basic tools you can use to make your searching more quick and effective-and to save you the time and effort of wading through a long list of sources to find the ones you can use.

The three most common operators are AND, OR, and NOT. XOR is another operator you find available when using some databases, including the LSU Libraries Online Catalog. Each operator does something slightly different.

AND

AND links terms together in a way that makes your search more narrow. Using AND tells the computer that you want records that contain all the words you specify. For instance, the following search will find you only records that contain the words "dog" and "cat":

dog and cat

If the record contains only the word "dog", it won't show up. Likewise, if it only contains the word "cat", the search will ignore it. The record has to contain both terms for the search to return it.

Although you can use AND to link together as many terms as you want, the more times you use AND, the more narrow your search gets, and the fewer records your search will turn up. For instance, a search on dog and cat and snake would turn up less records than one for dog and cat.

This is sometimes difficult to conceptualize, so here's a visual representation of what an AND search would look like. Think of circle "A" as representing all the records that contain the word "dog", and circle "B" as representing all the records that contain the word "cat."

The purple space where they intersect represents all the records that would be returned by the search dog and cat.

results of an AND search

OR

OR is, in some ways, the exact opposite of AND. Instead of narrowing a search, OR widens it by turning up records that have either term you specify.

For instance, a search on dog or cat will get you all the records that contain the word "dog", as well as all the ones that contain the word "cat".

Although at first glance this may not seem very useful, it can come in very handy in certain situations. For instance, a search on "dog" will only get you records that have the word "dog", not "dogs", "canines" or "canis domesticus", all of which are terms used for "dog." So if you wanted all the possible records that might be about dogs, you could try dog or dogs or canines or canis domesticus.

Here's a visual representation of an OR search. Again, one circle would be all the records containing the word "cat", and the other all the records containing the word "dog." As you can see, OR merges two searches into one, increasing the number of matches.

The purple space represents all the records that would be returned by the search "dog or cat."

NOT

Finally, NOT is a term that allows you to exclude records with certain words from your search. Specifying dogs not cats would get you all the records that contain the word "dogs" EXCEPT the ones that also contain the word "cats." For instance, if we had a book whose title was "The Complete Book of Dogs and Cats", that record would not show up, even though it had the word "dogs" in it, because it also contains the word "cats."

This can be helpful if you want to exclude certain records from your search. Let's say I was looking for books on the state of Mississippi, and typed in Mississippi as a keyword search. I'd get a lot of books on the Mississippi river, so I type in Mississippi not river, which effectively cuts out all the books on the Mississippi River. Be cautious with this term-you can cut out a lot of records you might want. Think carefully when using it!

Here are visual representations of NOT searches. Notice that it does make a difference which order your search terms are placed. "Dog not cat" returns very different results than "cat not dog."

The purple spaces represent all the records that would be returned by the search "dog not cat," and "cat not dog."

XOR

The last operator we will cover here is the "XOR," or the "exclusive or" operator. XOR is used to locate records matching any of the specified terms but not all of the specified terms. For example, "dogs XOR cats" will find items with the word "dog" or the word "cat" in the record, but will not return items which have both terms in the record.

A or B, excluding A and B

The purple space represents all the records that would be returned by the search "dog xor cat."

Combining Terms

You can get really fancy with your searching by combining different boolean connectors in different ways. For instance, here's what I use when I need to find a dictionary or encyclopedia of Greek mythology:

(dictionary or encyclopedia) and greek and mythology

This will pull up any record in the computer that has the words "Greek" and "mythology" and either "dictionary" or "encyclopedia" somewhere in it. When combining boolean terms, you usually need to enclose separate parts of the search in parentheses, which is called grouping, and a group of words connected by boolean terms inside parentheses is called a set.

Here's another example of a search for materials on depression and schizophrenia in children and adolescents, using AND to combine two sets:

(depression or schizophrenia) and (child or children or adolescent or young adult)

Final Words on Boolean Searching

While many online library catalogs, databases, and Internet search engines support boolean searching, not all of them actually use the terms AND, OR, and NOT. Some may use the plus sign(+), slash(/), and minus sign(-), respectively. You can usually check the help files to find out if this is the case.

Also, some may support other terms like NEAR, WITH, or ADJ. These are called proximity indicators, because what they do is tell the database to look for terms based on how close together or far apart they are. These terms are not as universal as the three I've shown you, so you'll need to check the database help files to see how they work.

Truncation

Truncation is a way of using generic characters to "stand in" for letters if you are unsure of spelling or want words with different endings.

Exactly how truncation works depends on the particular database. Some allow truncation in the middle of the word, some only at the end. Some allow truncation at the beginning of the word (allowing you to search for anything that ends in -ide, for example, like chloride or sulfide), but that is rare. Usually, a truncation symbol in the middle of a word can stand in for one or no characters, and one at the end of the word can stand for any number of characters.

Most often, the truncation characters will be an asterisk (*), a question mark (?), or a dollar sign ($) but you'll need to check the help files for the particular database to see which one.

The real strength of truncation is pulling up related words with different endings.

Let's say we needed to search for any and everything on librarianship. We might type in librar?, which would bring up librarian, librarianship, library, and anything else that began with the letters librar.

Beware! Think carefully before you stick a truncation mark in your search. If you don't put enough characters before or after the mark, you'll be inundated with matches. Do a search on cat? and you'll get records containing the words cat, cats, catastrophe, catenate, category, catalog, catatonic, and on, and on, and on...

Fields and Field Searching

Computer databases offer powerful search opportunities because they can search a tremendous number of records at once, and because they offer the opportunity for very specific searches that you can't do with print sources.

Part of the reason online databases can offer this kind of searching flexibility is the concept of fields. A field is a specific, standardized part of a record in which a piece of information is entered.

Let's take an example. A periodical citation (say, in a works cited list) always has certain specific pieces of information: the author of the article, the title of the article, the journal in which the article appeared, the date the journal was published, the volume number of the journal, and the page numbers of the article.

Since all periodical citations have this information, databases of periodical citations set up fields for this information, and for other pieces of information that the database may keep on the article, like the abstract (a short summary of the article) and the descriptors or subject headings.

So why should you care? Because in most online databases, you can specify in your search which field you want searched. If we know the author of an article, we can type in the name and use some convention to make the database search only the author field for his name, rather than all the parts of the citation.

Finish

You have now been exposed to some Techniques and Strategies that will help you perform more successful online searches. Remember to check the help files for the database you are using if you are unfamiliar with the way it searches.

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