Perhaps you should try some spelling variations:
filosofia le » filosofia de, filosofia del, filosofia da
filosofia e » filosofia de, filosofia del
studium da » studium das, studium d, studium der
studium a » studium am, studium ad, studium _
test des » test der, test test

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

• If you are trying to use Boolean operators, they must be ALL CAPS: test des ((studium da) OR (studium a)) ((filosofia le) OR (filosofia e)) litterature.
• The words AND, OR and NOT may confuse the search; try adding quotes: "test des ((studium da) OR (studium a)) ((filosofia le) or (filosofia e)) litterature".
• Adding a wildcard symbol may retrieve word variants: test des ((studium da) OR (studium a)) ((filosofia le) or (filosofia e)) litterature*.