Perhaps you should try some spelling variations:
suitable studies » table studies, unstable studies, suitability studies
test suitable » best suitable, most suitable, notes suitable
filosofia da » filosofia de, filosofia e, filosofia della
studies die » studie die, studien die, studies does

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 suitable studies die ((filosofia da) OR (filosofia del)) literatura*.