Perhaps you should try some spelling variations:
passiv » passive, passiver
passiven » passiveen, passiveren, passive, passion
passiveeren » passiveeeren, passivereeren, passivieren, passieren, passiverer
massiv » massive
massigen » massiger, massigung, massie, massigern, massign
massige » massiger, massig

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