Perhaps you should try some spelling variations:
radio communications » radio communication, data communications
des developpements » deux developpements, de developpement, et developpements
developpements en » developpement en, developpement et, developpements de
variation der » variation des, variation bei, variation _
typologie de » typologie des, typologie der, typologien der
de variation » der variation, die variation, does variation
does radio » das radio

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

• Adding a wildcard symbol may retrieve word variants: typologie de variation der does radio communications _ des developpements en afrique.*.