Perhaps you should try some spelling variations:
filosofica da » filosofia da, filosofia de, filosofia di
da literatura » la literatura, a literatura, de literatura
tests stable » tests table, sets stable, test table
studien die » studie die, studien der
studien de » studien der, 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 stable ((studien de) OR (studien die)) filosofica da literatura".
• Adding a wildcard symbol may retrieve word variants: tests stable ((studien de) OR (studien die)) filosofica da literatura*.