Perhaps you should try some spelling variations:
sprachen studien » sprachsinn studien, sprachen die, rischen studien
filosofia da » filosofia de, filosofia del, filosofia e
filologia a » filologia e, filologica e, filologici e
studien de » studien der, studien die, studien des
rats » rate, rays

You may be able to get more results by adjusting your search query.

• If you are trying to use Boolean operators, they must be ALL CAPS: (rats OR rat) sprachen studien de ((filologia a) OR (filosofia da)) literature.
• The words AND, OR and NOT may confuse the search; try adding quotes: "(rats or rat) sprachen studien de ((filologia a) OR (filosofia da)) literature".
• Adding a wildcard symbol may retrieve word variants: (rats or rat) sprachen studien de ((filologia a) OR (filosofia da)) literature*.