Perhaps you should try some spelling variations:
e literatura » de literatura, y literatura, e literatur
studies die » studien die, studies does, studies dose
filosofia e » filosofia de, filosofia del
tests case » test case, tests based, test cases
studie die » studie 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: "tests case ((studies die) OR (studie die)) filosofia e literatura".
• Adding a wildcard symbol may retrieve word variants: tests case ((studies die) OR (studie die)) filosofia e literatura*.