Combining Your Search Terms
Now that you have prepared what sources you want to find, the keywords you want to use to conduct your searches, and the databases you want to look in, you can start searching!
Many databases use what are called Boolean operators (AND, OR, and NOT) to establish relationships between your selected keywords to limit, broaden, or define the search results.
AND
Using AND will narrow your search by only pulling up results that include BOTH keywords.
OR
Using OR will broaden your search by pulling up results that include EITHER one of the keywords or BOTH of the keywords. OR is also a great Boolean Operator to use when you have a certain subject or topic that has several similar terms to describe it.
NOT
Using NOT will restrict your search results by excluding the term that directly follows NOT. This is an excellent operator to use when your search results are pulling up a lot of irrelevant results (perhaps a keyword has multiple meanings; you can use NOT to specify which definition you DON'T want included in the search results).
Search Precedence
The way you search with Boolean Operators MATTERS. Most databases will search keywords that are linked with AND first. This means that if you have any terms linked together by OR that you want to have searched first, you will need to group them together within parentheses (). Otherwise, the two words connected by AND will be searched first.
Example: ("Great War" OR "World War 1") AND trenches