Perhaps you should try some spelling variations:
opec communication » open communication, optic communication, ec communication
does developpement » de developpement, des developpements, does development
developpement de » developpement des, developpement durable
typologien der » typologie der, typologie des, apologien der
der variation » de variation, does variation, die variation
variation 6 » variation _, variations _, variation des
der opec » der oper, des opec, der opfer
a does » 2 does, 4 does, 1 does
6 der » _ der, 2 der, 3 der

You may be able to get more results by adjusting your search query.

• Adding a wildcard symbol may retrieve word variants: typologien der variation 6 der opec communication a does developpement de l'afrique.*.