"Using the Databases." Research - Expert Level. Crossett Library at Bennington College. 13 May 2016. Web. 3 August 2016.
Boolean searching is a method of searching that allows you to narrow or broaden your search results. It can help filter out the results that don't really contain the information you are looking for and keep the ones that do or expand your search by allowing you to search multiple synonyms of a word at once. Students that master Boolean searching skills will more efficiently find resources that suit their purposes.
The first step in the process is to write down all of the search terms you plan on using. For example, if you are researching the impact smoking has on the grades of teenagers, some search terms might be: smoking, grades, and teenagers. The next step is to think about any synonyms for those terms. For example, synonyms of the above terms could be cigarettes, education, teens, students, adolescents. and many, many more.
Understanding the concept of connectors is the way to master Boolean searching.
AND is a limiter. It should be used when you have too many search results and you want to narrow them down a bit.
For example, searching just the term "teenagers" would bring back way too many results that would include any article about teenagers, not specifically the articles on teens, smoking, and grades that you are looking for. By searching "teenagers AND smoking" you will narrow down your results further to include only the articles about teenagers and smoking rather than anything and everything about teenagers. If you still have way too many results, you can add another keyword to narrow further such as "teenagers AND smoking AND grades." This will filter out the articles that are about the physical impact of smoking in teens, for example.
OR is an expander. It should be used when you are using a search term with synonyms.
For example, you might search "teenagers OR adolescents" in order to get articles that use either term rather than performing separate searches with each term.
NOT is a limiter. It should be used when you are using a search term with multiple meanings.
Using a different example, you might search "jaguars NOT automobiles" if you want articles about the animal rather than the car. This will filter out those articles about the car, leaving the ones about the animal.
To combine Boolean operators, you must use parentheses to tell the database which order to recognize the operators. Everything inside the parentheses is recognized first. So, to get results about mousetraps that refer to the animal as either a mouse or a rat, you would write your search string like this: (mouse OR rat) AND trap.
Additionally, you can do a truncation search. Most of our databases do this with an asterisk, though it varies by database. So if you wanted to search multiple versions of children, you would make your search term "child*". This would search the word child, but also children. Another example is "recruit*" which would search recruit as well as the various endings such as recruitment and recruiting.
Finally, if you are searching a phrase rather than a single term, put that phrase in quotation marks. So student recruitment would be searched "student recruitment". This would give you results that have those two words together as a phrase rather than results that also have those two terms in them but not necessarily together. Other examples would be "user experience" or "customer satisfaction".