Perhaps you should try some spelling variations:
del literatura » de literatura, pela literatura, e literatura
da literatura » la literatura, a literatura, de literatura
case studies » case study
a filosofia » la filosofia, e filosofia, di filosofia
tests case » test case, tests based, test cases

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: "tests case studies a filosofia ((del literatura) OR (da literatura))*".