Perhaps you should try some spelling variations:
mathematika » mathematica, mathematical, mathematicae
mathematicala » mathematical, mathematicals, mathematicaland
mathematikers » mathematikern
mathematiklernen » mathematikern, mathematiklehrerinnen
mathematiklehrer » mathematikern

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 mathematicala) OR mathematik) OR ((mathematikers OR mathematiklernen) OR (mathematiklehrer OR mathematiker))).
• The words AND, OR and NOT may confuse the search; try adding quotes: "(((mathematika or mathematicala) or mathematik) or ((mathematikers OR mathematiklernen) or (mathematiklehrer or mathematiker)))".
• Adding a wildcard symbol may retrieve word variants: (((mathematika or mathematicala) or mathematik) or ((mathematikers OR mathematiklernen) or (mathematiklehrer or mathematiker)))*.