Perhaps you should try some spelling variations:
passiv » massiv, passiver
passive » massive, passivere
passiven » massiven, passiveren
passiverer » 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 passive) OR (((passiven OR passion) OR passiverer) OR massiveren)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((passiv or passive) or (((passiven OR passion) or passiverer) or massiveren))".
• Adding a wildcard symbol may retrieve word variants: ((passiv or passive) or (((passiven OR passion) or passiverer) or massiveren))*.