Perhaps you should try some spelling variations:
communications costs » communication costs, communications _
technology change » technological change, technological changes
change simulation » change simulations, channel simulation, change population
simulation rules » simulation les, simulation results, simulation des
4 communications » 14 communications, 4 communication, 2 communications
developpement il » developpement de, developpement et, developpement du
a developpement » au developpement, de developpement, le developpement
il afrique » l afrique, en afrique
trade 4 » trade _, trade a
costs a » costs _, costs 4

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

• Adding a wildcard symbol may retrieve word variants: technology change simulation rules trade 4 communications costs a developpement il afrique.*.