Perhaps you should try some spelling variations:
de literatura » de litterature, la literatura, y literatura
di filosofica » de filosofia, da filosofia, e filosofica
case studies » case study
di filosofia » la filosofia, e filosofia
best case » test case

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: best case studies ((di filosofica) OR (di filosofia)) de literatura.
• Adding a wildcard symbol may retrieve word variants: best case studies ((di filosofica) or (di filosofia)) de literatura*.