Perhaps you should try some spelling variations:
del literatura » de literatura, pela literatura, da literatura
des studenten » der studenten, den studenten, die studenten
y filosoficos » y filosofia, e filosofica, e filosofiche
y filosofico » y filosofia, e filosofica, e filosofiche
test des » test der, test test

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 des studenten ((y filosoficos) OR (y filosofico)) del literatura*".