Perhaps you should try some spelling variations:
passiv » passiven, passiver
passive » passivene, passivere
passiveeren » passiveneeren, passivereeren, passivieren, passieren, passivierende
passiverer » passivenerer, passivererer, passiverwerb, passivieren, passiver
massiv » massive
massiven » massiveen, massive, passiven, massively
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 ((passive OR massiven) OR (massigen OR (passiveeren OR passiverer)))).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((passiv OR massiv) or ((passive or massiven) or (massigen or (passiveeren or passiverer))))".
• Adding a wildcard symbol may retrieve word variants: ((passiv OR massiv) or ((passive or massiven) or (massigen or (passiveeren or passiverer))))*.