Perhaps you should try some spelling variations:
delle studien » delphi studien, modell studien, die studien
duale studien » duale studium, scale studien, duales studium
der filosofia » de filosofia, e filosofia, di filosofia
de literatura » de litterature, la literatura, y literatura
filosofia de » filosofia del

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 ((delle studien) OR (duale studien)) der filosofia de literatura.
• Adding a wildcard symbol may retrieve word variants: test ((delle studien) or (duale studien)) der filosofia de literatura*.