Perhaps you should try some spelling variations:
2 filosoficos » y filosoficos, e filosofica, e filosofiche
y filosofico » y filosoficos, y filosofia, e filosofica
a literatura » la literatura, a literature, y literatura
zu studie » zu studien, eu studies, zu studium
test zu » test zur, tests zu, test zum

You may be able to get more results by adjusting your search query.

• The words AND, OR and NOT may confuse the search; try adding quotes: "test zu studie ((2 filosoficos) OR (y filosofico)) a literatura*".