Perhaps you should try some spelling variations:
passiver » passive, passiven, passively
massiv » massive
massiveeren » massiveeeren, massivere, massivdecken, massivteilen
passivieren » passivierende, passivierung, passieren
passiveneren » passieren, passiverer
massigeren » massiger, massigen, massivere

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 massiv) OR ((passivieren OR passiveneren) OR (massigeren OR massiveeren))).
• Adding a wildcard symbol may retrieve word variants: ((passiver or massiv) or ((passivieren or passiveneren) or (massigeren or massiveeren)))*.