Perhaps you should try some spelling variations:
de filosofica » de filosofia, e filosofica, e filosofia
filosofica da » filosofia da, filosofia de, filosofia di
da literatura » la literatura, a literatura, de literatura
tests stable » tests table, sets stable, test table
tests scale » sets scale, tests safe, tests shall
studien de » studien der, studien die, studien des

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