Perhaps you should try some spelling variations:
fuel literature » abel literature, level literature, model literature
filosofia fuel » filosofia del, filosofia de, filosofia e
text fishes » text files, text figures, great fishes
studies das » studies ds, studien das, studies data
studie das » studie des, studie der, studie am

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: "text fishes ((studies das) OR (studie das)) filosofia fuel literature".
• Adding a wildcard symbol may retrieve word variants: text fishes ((studies das) OR (studie das)) filosofia fuel literature*.