Perhaps you should try some spelling variations:
a literatura » la literatura, a literature, a literatur
y literatura » la literatura
vivo studie » vivo studies, vivo study
test vivo » test video, test via, test viii

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 vivo studie _ filosofica ((a literatura) OR (y literatura)).
• Adding a wildcard symbol may retrieve word variants: test vivo studie _ filosofica ((a literatura) or (y literatura))*.