Perhaps you should try some spelling variations:
passiver » passive, passiert
passivere » passivee, passierte, passiverer, massivere, passivieren
passiven » passive, passion
passives » passive, passions, passiv
passively » massively, passive, passivity

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