Perhaps you should try some spelling variations:
5.2 communication » 3.2 communication, 6.2 communication, 2.2 communication
developpement en » developpement et, developpement des, developpement de
technology area » technology arena, technology array, technology age
area population » a population, farm population, la population
4 developpement » de developpement, le developpement, et developpement
population per » population panel, population p230, population area
per fig » per firm
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: technology area population per fig 5.2 communication costs 4 developpement en afrique.*.