Perhaps you should try some spelling variations:
passiv » passive, massiv, passiven
passiveen » passiveeen, massiveen, passiveneen, passiven, passiveand, passiverer
passivieren » passiveieren, massivieren, passivenieren, passivierende, passieren, passagieren
passivierung » passiveierung, massivierung, passivenierung, aktivierung
massigeren » massiger, massigen, massivere
massiveeren » massivere, massivdecken, massivteilen

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 passiveen) OR ((passivieren OR passivierung) OR (massigeren OR massiveeren))).
• Adding a wildcard symbol may retrieve word variants: ((passiv or passiveen) or ((passivieren or passivierung) or (massigeren or massiveeren)))*.