Perhaps you should try some spelling variations:
di literatura » de literatura, da literatura, ii literatura
case studies » case study
ds filosofia » di filosofia, de filosofia, da filosofia
filosofia di » filosofia de, filosofia da, filosofia del
test » text

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 ((case studies) OR (scale study)) ds filosofia di literatura.
• Adding a wildcard symbol may retrieve word variants: test ((case studies) or (scale study)) ds filosofia di literatura*.