Perhaps you should try some spelling variations:
mathematika » mathematik, mathematica, mathematical
mathematikums » mathematikers, mathematikbuch, mathematik
mathematikund » mathematikbuch, mathematik, mathematikern
mathematiker » mathematik

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: ((mathematika OR mathematikums) OR (mathematikund OR mathematiker))*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((mathematika or mathematikums) or (mathematikund OR mathematiker))*".