Keywords may be separated by AND and/or OR statements for greater control of the search results.
For example, Verdi AND sonata would generate a result set that contain both words. However, for Verdi OR sonata, the result set returned would contain both or either words.
Exact matches can be searched for by enclosing more keywords in double-quotes.
For example, "Monteverdi, Claudio" would generate a result set which match the exact string.
Brackets can be used for further control on the result set.
For example, Verdi and (sonata or sinfonia or "doppio concerto").