Perhaps you should try some spelling variations:
y literatura » la literatura
peer studie » peer studies, peers studien, der studie
a filosofia » la filosofia, di filosofia
e filosofia » la filosofia
best peer » best peere, best peep, best paper

You may be able to get more results by adjusting your search query.

• The words AND, OR and NOT may confuse the search; try adding quotes: "best peer studie ((a filosofia) OR (e filosofia)) y literatura".
• Adding a wildcard symbol may retrieve word variants: best peer studie ((a filosofia) OR (e filosofia)) y literatura*.