Perhaps you should try some spelling variations:
la literatura » la litterature, a literature
filosofia la » filosofia da, filosofia le, filosofica da
tests scale » tests stable, sets scale, tests shall
tests safe » tests safety, tests space, tests tafel
studien la » studien lap, studien a, studien l

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