Perhaps you should try some spelling variations:
de literatura » de litterature, la literatura, y literatura
duale studium » duales studium, dualen studium, das studium
de filosofia » e filosofia, la filosofia, a filosofia
di filosofia » la filosofia, e filosofia
test duale » test double, test delle, test orale

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 duale studium ((de filosofia) OR (di filosofia)) de literatura*.