Perhaps you should try some spelling variations:
formulation validation » population validation, formulation verification, formulation solution
data communication » data communications
validation costs » validation tests, evaluation costs, validation tools
developing eco » developing e, developing ict, developing ce
4 developing » 3 developing
eco afrique » en afrique
costs 4 » costs _, costs a, costs 4.2
media 4 » media _, media 1, media 3

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

• Adding a wildcard symbol may retrieve word variants: policy formulation validation costs 4 data communication media 4 developing eco afrique.*.