Perhaps you should try some spelling variations:
de litterature » la litterature, et litterature
filosofica de » filosoficas de, filosofia de, filosofica da
texts data » text data, contexts data, textual data
texts das » text das, texten das, texts adam
studium e » studium 1, studium 3, studium 8

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: ((texts das) OR (texts data)) ((studium e) OR (studium _)) filosofica de litterature.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((texts das) OR (texts data)) ((studium e) or (studium _)) filosofica de litterature".
• Adding a wildcard symbol may retrieve word variants: ((texts das) OR (texts data)) ((studium e) or (studium _)) filosofica de litterature*.