Perhaps you should try some spelling variations:
passiver » passive, passively, passiert
passiverer » passiveer, passivelyer, passierter, passiverwerb, passivieren, passieren
passiven » passive, passion
massiveren » massivere, massivement, passivieren
massigeren » massiger, massigen, massivere
passiveeren » passivieren, passieren, passivierende

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: (passiver OR (passiven OR ((massiveren OR massigeren) OR (passiveeren OR passiverer)))).
• The words AND, OR and NOT may confuse the search; try adding quotes: "(passiver or (passiven or ((massiveren or massigeren) or (passiveeren OR passiverer))))".
• Adding a wildcard symbol may retrieve word variants: (passiver or (passiven or ((massiveren or massigeren) or (passiveeren OR passiverer))))*.