Perhaps you should try some spelling variations:
communication barriers » communication series, communication disorders
key developpement » de developpement, le developpement, et developpement
developpement de » developpement des, developpement durable
formulation de » formulation des, formulacion de, formulation du
barriers key » barriers been, barriers _, barriers a
de afrique » de l'afrique, en afrique, l afrique
de does » der does, do does, one does

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

• Adding a wildcard symbol may retrieve word variants: technologies _ formulation de does risk communication barriers key developpement de afrique.*.