Perhaps you should try some spelling variations:
passiv » passive, passiven, passiver
passivieren » passiveieren, passivenieren, passiverieren, passivierende, passivierung, passagieren
massiv » massive
massivere » massiveere, massiver, massive, massively
passieren » passiert, passiven
massigen » massiger, massige, massigung

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