Perhaps you should try some spelling variations:
la litterature » a literature
test failure » test failures, post failure, fast failure
filosofia la » filosofia da, filosofia le, filosofica da
studies das » studies ds, studie das, studies data
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 la litterature.
• Adding a wildcard symbol may retrieve word variants: test failure ((studies das) or (studien das)) filosofia la litterature*.