OR is the default conjunction operator. This means that if there is no Boolean operator between two terms, the OR operator is automatically used. The OR operator links two terms and finds a matching document if either of the terms exist in a document.
For example, to search for a work that contains either Theremin or Electronic, use one of the following search queries:
REMEMBER: OR MEANS MORE!
The AND operator matches documents where both terms exist anywhere in the text of a single document. Therefore, using AND will limit the number of returned results.
To search for a work that contains the piccolo and the piano, use the search query:
"piccolo" AND "piano"
The NOT operator excludes documents that contain the term after NOT. To search for a percussion piece excluding the djembe, use the search query:
"percussion" NOT "djembe"
Note: The NOT operator cannot be used with just one term. For example, the following search will return no results: NOT "string quartet"