Perhaps you should try some spelling variations:
da literatura » la literatura, a literatura, de literatura
filosofia da » filosofia de, filosofia del, filosofia e
sets scale » sets scaled, sets scales, set scale
studies dd » studies d, studies dn, studies dc

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: "sets scale ((studies dd) OR (studies ds)) filosofia da literatura".
• Adding a wildcard symbol may retrieve word variants: sets scale ((studies dd) OR (studies ds)) filosofia da literatura*.