Perhaps you should try some spelling variations:
le literatura » la literatura, de literatura, e literatura
tests safety » test safety, guests safety, stents safety
filosofia le » filosofia de, filosofia e, filosofia del
study law » study low
study la » study lay, study lca, study lia

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 safety ((study la) OR (study law)) filosofia le literatura".
• Adding a wildcard symbol may retrieve word variants: tests safety ((study la) OR (study law)) filosofia le literatura*.