Boolean Searching

You may use the words AND,OR,NOT and surround statements in brackets on any field in order to better define your search parameters

NOT Gloria will return everything without the world 'Gloria' in it.
Bach OR Josquin will return both items with 'Bach' and items with 'Josquin'.
Bach AND Josquin will probably return nothing, as this will return only items that have 'Bach' and 'Josquin' in them.
G Minor AND NOT(Gloria OR Sanctus) will only return items tagged with 'G Minor' and which are also not tagged with either 'Gloria' or 'Sanctus'