Perhaps you should try some spelling variations:
della letteratura » nella letteratura, e letteratura
filosofia della » filosofia del, filosofia de
during studies » docking studies, housing studies, aging studies
during studie » during study, during soldier, during static
e filosofia » la filosofia

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 ((during studie) OR (during studies)) e filosofia della letteratura*".