Perhaps you should try some spelling variations:
la literatura » la litterature, a literature
peers studien » peer studie, peer studies, plebs studien
am filosofia » a filosofia, em filosofia, la filosofia
best peers » best peer, best peere, best papers
studien am » studien a, studien aus, studien auf

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 peers studien am filosofia ((y literatura) OR (la literatura)).
• Adding a wildcard symbol may retrieve word variants: best peers studien am filosofia ((y literatura) or (la literatura))*.