Perhaps you should try some spelling variations:
der filosofia » de filosofia, e filosofia, di filosofia
de literatura » de litterature, la literatura, y literatura
filosofia de » filosofia del
tests scale » tests stable, tests safe, tests shall
studien der » studie der, studien die, studenten der
sets scale » sets scaled, sets scales, set scale

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 scale) OR (sets scale)) studien der filosofia de literatura".
• Adding a wildcard symbol may retrieve word variants: ((tests scale) OR (sets scale)) studien der filosofia de literatura*.