Perhaps you should try some spelling variations:
passiv » passive, massiv, passiven
passivieren » passiveieren, massivieren, passivenieren, passivierende, passivierung, passieren
passiverer » passiveerer, massiverer, passivenerer, passiver, passieren, passagerer
passiverwerb » passiveerwerb, massiverwerb, passivenerwerb
massiven » massive, passiven, massively
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 (massiven OR (massiveren OR (passivieren OR (passiverer OR passiverwerb))))).
• The words AND, OR and NOT may confuse the search; try adding quotes: "(passiv or (massiven or (massiveren or (passivieren or (passiverer OR passiverwerb)))))".
• Adding a wildcard symbol may retrieve word variants: (passiv or (massiven or (massiveren or (passivieren or (passiverer OR passiverwerb)))))*.