Perhaps you should try some spelling variations:
orale studien » duale studien, frage studien, scale studien
le literatura » la literatura, de literatura, e literatura
da filosofia » di filosofia, a filosofia, de filosofia
test orale » test oracle, test oral, test oracles

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 orale studien ((la filosofia) OR (da filosofia)) le literatura.
• Adding a wildcard symbol may retrieve word variants: test orale studien ((la filosofia) or (da filosofia)) le literatura*.