Perhaps you should try some spelling variations:
opec communication » open communication, optic communication, ec communication
der developpements » des developpements, deux developpements, de developpement
developpements l » developpements de, developpement il, developpement la
variation des » variation _, variation 6, variation series
l afrique » en afrique
dr opec » der opec, der oper, des opec
a 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: typology _ variation des dr opec communication a der developpements l afrique.*.