Perhaps you should try some spelling variations:
scales studien » scale studien, scale studies, scale student
di literatura » de literatura, da literatura, ii literatura
case studies » case study
filosofia di » filosofia de, filosofia da, filosofia del
e filosofia » la filosofia

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: sets ((scales studien) OR (case studies)) e filosofia di literatura.
• Adding a wildcard symbol may retrieve word variants: sets ((scales studien) or (case studies)) e filosofia di literatura*.