Perhaps you should try some spelling variations:
duale studien » duale studium, scale studien, duales studium
de filosofia » di filosofia, la filosofia, a filosofia
y literatura » la literatura
e filosofia » la filosofia
testo » test, tests, texto

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: testo duale studien ((e filosofia) OR (de filosofia)) y literatura.
• Adding a wildcard symbol may retrieve word variants: testo duale studien ((e filosofia) or (de filosofia)) y literatura*.