Perhaps you should try some spelling variations:
le literatura » la literatura, de literatura, e literatura
oral studies » coral studies, rural studies, viral studies
d filosofia » di filosofia, de filosofia, da filosofia
test oral » test oracle, test orn, 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 oral studies ((d filosofia) OR (la filosofia)) le literatura*.