Perhaps you should try some spelling variations:
communication barriers » communication series, communication disorders
developpement en » developpement et, developpement des, developpement de
3 communication » 4 communication, de communication, data communication
4 developpement » de developpement, le developpement, et developpement
formulation de » formulation des, formulacion de, formulation du
barriers 4 » barriers _, barriers a, barrier _
de doses » des doses, _ doses, de deces
doses 3 » doses _, doses et, drones 3

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

• Adding a wildcard symbol may retrieve word variants: technologies _ formulation de doses 3 communication barriers 4 developpement en afrique.*.