Perhaps you should try some spelling variations:
does developpement » de developpement, des developpements, does development
developpement l » developpement il, developpement la, developpement de
variation des » variation _, variation 6, variation series
l afrique » en afrique
die opec » die oper, die opfer, die opera
die open » die typen, die opfer, use open
a does » 2 does, 4 does, 1 does

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

• The words AND, OR and NOT may confuse the search; try adding quotes: "typology _ variation des ((die opec) OR (die open)) communication a does developpement l afrique.~".
• Adding a wildcard symbol may retrieve word variants: typology _ variation des ((die opec) OR (die open)) communication a does developpement l afrique.*.