Perhaps you should try some spelling variations:
studenten der » studenten und
studenten de » studenten des, studenten die, studenten das
filosofia e » filosofia de, filosofia del
e literatur » die literatur
test von » testen von

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 von ((studenten de) OR (studenten der)) filosofia e literatur*".