Perhaps you should try some spelling variations:
"related studies; grundkurs informatik" » "related species; grundkurs informatik"
"viewed studium; bruckenkurs mathematik" » "reviewed studies; bruckenkurs mathematik"

Try widening your search to All Fields.

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: (((("vieweg studium; grundkurs mathematik") OR ("vieweg studium; vorkurs mathematik"))) OR ((("viewed studium; bruckenkurs mathematik") OR ("related studies; grundkurs informatik")))).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((\"vieweg studium; grundkurs mathematik\") OR (\"vieweg studium; vorkurs mathematik\"))) or (((\"viewed studium; bruckenkurs mathematik\") or (\"related studies; grundkurs informatik\"))))".
• Removing quotes may allow a broader search: (((( vieweg studium; grundkurs mathematik ) OR ( vieweg studium; vorkurs mathematik ))) or ((( viewed studium; bruckenkurs mathematik ) or ( related studies; grundkurs informatik )))).
• Adding a wildcard symbol may retrieve word variants: (((("vieweg studium; grundkurs mathematik") OR ("vieweg studium; vorkurs mathematik"))) or ((("viewed studium; bruckenkurs mathematik") or ("related studies; grundkurs informatik"))))*.