Perhaps you should try some spelling variations:
del literatura » de literatura, pela literatura, da literatura
der filosofia » de filosofia, e filosofia, di filosofia
sets scaled » sets scales, less scaled, sets khaled
studien der » studie der, studenten der
sets scale » sets scales, set scale, sets stable

You may be able to get more results by adjusting your search query.

• If you are trying to use Boolean operators, they must be ALL CAPS: ((((sets scale) OR (sets scaled))) OR (((sets scale) OR (sets scaled))s)) studien der filosofia del literatura.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((sets scale) OR (sets scaled))) or (((sets scale) OR (sets scaled))s)) studien der filosofia del literatura".
• Adding a wildcard symbol may retrieve word variants: ((((sets scale) OR (sets scaled))) or (((sets scale) OR (sets scaled))s)) studien der filosofia del literatura*.