Perhaps you should try some spelling variations:
oral communication » personal communication
leur developpement » le developpement, deux developpements, de developpement
developpement de » developpement des, developpement durable
typologien does » typologie des, typologien der, typologie der
does variation » de variation, der variation, die variation
rates oral » rates formal, rates rural, rates brazil
de afrique » de l'afrique, en afrique, l afrique

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

• Adding a wildcard symbol may retrieve word variants: typologien does variation _ rates oral communication a leur developpement de afrique.*.