Perhaps you should try some spelling variations:
filosofia le » filosofia de, filosofia del, filosofia da
des studium » des studiums, das studium, dem studium
filosofia e » filosofia de, filosofia del
studium da » studium das, studium a, studium d
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 studium da ((filosofia le) OR (filosofia e)) litterature".
• Adding a wildcard symbol may retrieve word variants: test des studium da ((filosofia le) OR (filosofia e)) litterature*.