Perhaps you should try some spelling variations:
passiv » passive, massiv, passiver
passiven » passiveen, massiven, passiveren, passive, passion
passiveren » passiveeren, massiveren, passivereren, passivieren, passieren, passiver
passiverer » passiveerer, massiverer, passivererer, passiverwerb, passivieren, passiver
massiveren » massivere, massigeren, massivement

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 ((passiven OR passiveren) OR (massiveren OR passiverer)))*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "(passiv or ((passiven OR passiveren) or (massiveren or passiverer)))*".