Perhaps you should try some spelling variations:
delle studien » duale studien, delphi studien, modell studien
filosofia le » filosofia de, filosofia e, filosofia da
studien der » studie der, studien die, studenten der
tesi delle » testi delle, test delle, testi della

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: "tesi delle studien der ((filosofia le) OR (filosofia del)) literatura".
• Adding a wildcard symbol may retrieve word variants: tesi delle studien der ((filosofia le) OR (filosofia del)) literatura*.