Boolean operators allow you to combine your keywords to create a search that the databases can use to retrieve the results you need. The words AND, OR are the most commonly used Boolean operators. The third is NOT, which can be difficult to use because it might exclude useful results.
AND combines your search terms and looks for them together in search result. Example: A search for Leonardo da Vinci AND Michelangelo will retrieve records that have both keywords: Leonardo da Vinci and Michelangelo.
OR separates your search terms, finding records that contain either keyword. Example: A search for Leonardo da Vinci OR Michelangelo will retrieve records all the records that contain either of the search terms as well as records with both of the search terms.
NOT finds records that only have the first keyword, but will exclude records that have both keywords or just the second keyword. A search for Leonardo da Vinci NOT Michelangelo will find records only containing Leonardo da Vinci and will exclude records that also include Michelangelo or are only about him. This boolean operator is only useful when you want to exclude a topic that is often associated with your first keyword. For example, if you wanted articles about Leonardo da Vinci's paintings excluding the Mona Lisa, the search: Leonardo da Vinci NOT Mona Lisa. Just remember that this type of search is very narrow and might exclude records that also include information on your topic.
Truncation allows you to get more results out of your search term. This is especially useful when there are many ways that the same word can be expressed. By using the root letters of your word plus the symbol *-- you may be able to find everything you need in a single search.
When searching the words Christian AND symbol only finds 26 results
Searching Christian AND symbol* can find increase your results to 378 records.
Even better by searching Christian* AND symbol* you can find 428 records.
Phrase Searching helps you retrieve specific information in an exact order. This is especially helpful when your search words are commonly used and therefore will retrieve too many records that are off topic.
You can accomplish this by using "quotations marks" to enclose your keyword phrase.
For example: "Last Supper" rather than Last Supper
You might also be able to use a drop down menu or check box if the database you are using has a phrase search option.