Perhaps you should try some spelling variations:
2.2 communication » 2.3 communication, 3.2 communication, 2.7 communication
technology rate » technology state, technology role, technology related
rate population » create population, age population, male population
a developpement » au developpement, de developpement, le developpement
population per » population panel, population p230, population area
des afrique » en afrique, de l'afrique
per fig » per firm
fig 2.2 » fig 5.2, fig 2.1, fig 2.4
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 rate population per fig 2.2 communication costs a developpement des afrique.*.