Perhaps you should try some spelling variations:
filosofia le » filosofia de, filosofia e, filosofia del
have studie » have studied, have studies, wave studies
filosofia a » filosofia da, filosofia la, filosofia e
tests have » texts have, guests have, sets have
studie das » studie des, studie der, studie am

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: tests have studie das ((filosofia a) OR (filosofia le)) literature*.