Perhaps you should try some spelling variations:
tropen communication » open communication, proper communication, spoken communication
leur developpement » le developpement, deux developpements, de developpement
developpement de » developpement des, developpement durable
de variation » der variation, die variation, does variation
typology de » typology _, typology 6, typology a
variation 5 » variation _, variation 6, variation a
der tropen » den tropen, der treppen, der open
5 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 de variation 5 der tropen communication _ leur developpement de l'afrique.*.