Perhaps you should try some spelling variations:
y literatura » la literatura
paper studie » papers studies, paper sludge, paper study
a filosofia » la filosofia, di filosofia
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: best paper studie ((a filosofia) OR (e filosofia)) y literatura.
• Adding a wildcard symbol may retrieve word variants: best paper studie ((a filosofia) or (e filosofia)) y literatura*.