Perhaps you should try some spelling variations:
della literatura » della letteratura, pela literatura, nella letteratura
filosofia della » filosofia del, filosofia de
testing drug » testing during, testing data
studie die » studie der
studie de » studie der, studie des, studies de

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: "testing drug ((studie de) OR (studie die)) filosofia della literatura".
• Adding a wildcard symbol may retrieve word variants: testing drug ((studie de) OR (studie die)) filosofia della literatura*.