Perhaps you should try some spelling variations:
communications costs » communication costs, communications _
optimization under » optimization model, optimization models, optimization based
rate optimization » ratio optimization, state optimization, rank optimization
technology rate » technology state, technology role, technology related
3 developing » 3 development
developing l » developing l2, developing _, developing a
under case » under basel, gender case, under class
case data » cases data, base data, use data
l afrique » en afrique
costs 3 » costs _, costs 4, costs a

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

• Adding a wildcard symbol may retrieve word variants: technology rate optimization under case data communications costs 3 developing l afrique.*.