Perhaps you should try some spelling variations:
auf filosofia » a filosofia, su filosofia, alla filosofia
le literatura » la literatura, de literatura, e literatura
filosofia le » filosofia de, filosofia e, filosofia del
test modell » tekst modell, test models, text modell
studien auf » studien aus, studie auf
test model » test models, trust model, cost model

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: "((test modell) OR (test model)) studien auf filosofia le literatura".
• Adding a wildcard symbol may retrieve word variants: ((test modell) OR (test model)) studien auf filosofia le literatura*.