Perhaps you should try some spelling variations:
scale studien » scale studies, scale student, duale studien
filosofia de » filosofia del
tests scale » tests stable, sets scale, tests safe
studien der » studie der, studien die, studenten der
filosofia y » filosofia e, filosofia _, filosofia da

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