Perhaps you should try some spelling variations:
del literatur » model literatur, teil literatur, igel literatur
texts social » texas social, text social, texto social
tests social » test social, tests special, meets social
di filosofia » la filosofia, e filosofia
studien di » studien die, studien dd, studien der

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: "((texts social) OR (tests social)) studien di filosofia del literatur*".