Perhaps you should try some spelling variations:
communication barriere » communication barriers, communication series, communication based
technologies ret » technologies _, technologies 4, technologies 2
en developpement » et developpement, de developpement, le developpement
developpement en » developpement et, developpement des, developpement de
ret formulation » et formulation, re formulation, from formulation
formulation des » formation des, formulacion de, formulation _
barriere en » barriere der, barrieren und, barrieren der
des does » des doses, der does, des dorfes

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

• Adding a wildcard symbol may retrieve word variants: technologies ret formulation des does _ communication barriere en developpement en afrique.*.