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

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

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