Perhaps you should try some spelling variations:
passiv » passive, massiv, passiven
passivieren » passiveieren, massivieren, passivenieren, passivierende, passivierung, passieren
massivere » massiver, massive, massively
aktivierenden » motivierende, aktivierungden, motivierenden
aktivieren » aktivierung, motivieren

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