Perhaps you should try some spelling variations:
passiv » passive, massiv, passiver
passiven » passiveen, massiven, passiveren, passive, passion
passivieren » passiveieren, massivieren, passiverieren, passivierende, passivierung, passieren
massiveen » massiven, massivement, massivsten

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