Perhaps you should try some spelling variations:
passiv » passive, massiv, passiven
passiveere » passiveeere, massiveere, passiveneere, passivieren, passiver, massivere
aktivierende » aktivieren, motivierende, praktizierende
aktivierenden » aktivierenn, motivierenden, praktizierenden, aktivieren, motivierende

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: ((passiv OR passiveere) OR (aktivierende OR aktivierenden)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((passiv or passiveere) or (aktivierende OR aktivierenden))".
• Adding a wildcard symbol may retrieve word variants: ((passiv or passiveere) or (aktivierende OR aktivierenden))*.