Perhaps you should try some spelling variations:
filosofica da » filosofia da, filosofia de, filosofia di
da literatura » la literatura, a literatura, de literatura
tests scale » tests stable, sets scale, tests safe
studien der » studie der, studenten der
studien de » studien die, studien des, studien dd

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