Perhaps you should try some spelling variations:
modell studien » model studies, models studies, moderne studien
testi modell » test models, test model, tests models
filosofia la » filosofia da, filosofica da, filosofia das
filosofia le » filosofia de, filosofia e, filosofia del
studien a » studien am, studien _, studien 3

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: testi modell studien a ((filosofia la) OR (filosofia le)) literatura.
• Adding a wildcard symbol may retrieve word variants: testi modell studien a ((filosofia la) or (filosofia le)) literatura*.