Perhaps you should try some spelling variations:
massivieren » passivieren, massivere, passivierende
passivierung » aktivierung
massiveren » massivere, massivement, passivieren
massigeren » massiger, massigen, massivere
massiveeren » massivere, passivieren, massivdecken

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: (passive OR ((massivieren OR passivierung) OR ((massiveren OR massigeren) OR massiveeren))).
• Adding a wildcard symbol may retrieve word variants: (passive or ((massivieren or passivierung) or ((massiveren or massigeren) or massiveeren)))*.