Combining Search Terms
Computers use "Boolean Searching" to conduct searches. This refers to the use of one or more of three words ("operators") in searching. They are part of the drop down menu in the Advanced Search boxes.
The 3 words are AND, OR, and NOT. Use your keywords with the 3 different Boolean operators to narrow or broaden your search.
Use AND to narrow a search. Both terms (global warming and forests) must be present in any results you receive.
Use OR to expand your search. Hyperactivity and either term (children or adolescents)) will be in the results you receive. OR is used most often to combine synonyms of similar terms in a search, since different writers will use different terms.
Use NOT to exclude a term. Records with the first term (eating disorder) will be retrieved, but any records with the second term (bulimia) will be eliminated.
Truncation allows you to search for a root form of a word and pick up any ending. To use truncation, simply add the asterisk * sign to the end of any root form of a word. Truncation broadens your search. Just be careful where you truncate: "pol*" will pick up pollen, pollution, etc!
For example politic* will retrieve: