Perhaps you should try some spelling variations:
communications costs » communication costs, communications _
volume ventilation » volume estimation, volume variation
4.2 communications » 4.2 communication, 3.2 communication, 6.2 communication
seismology volume » technology volume
ventilation rate » ventilation strategy, ventilation system, ventilation modes
developpement en » developpement et, developpement des, developpement de
4 developpement » de developpement, le developpement, et developpement
rate case » state case, write case, rate caps
case 4.2 » case 4.1, case 2
costs 4 » costs _, costs a, costs 4.2

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

• Adding a wildcard symbol may retrieve word variants: seismology volume ventilation rate case 4.2 communications costs 4 developpement en afrique.*.