Perhaps you should try some spelling variations:
une litterature » de litterature, en litterature, one literature
filosofia une » filosofia de, filosofia e, filosofia en
test failure » test failures, post failure, fast failure
studies das » studie das, studies data, studies does
studien das » studie das, studien des, studien der

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 failure ((studies das) OR (studien das)) filosofia une litterature.
• Adding a wildcard symbol may retrieve word variants: test failure ((studies das) or (studien das)) filosofia une litterature*.