Perhaps you should try some spelling variations:
6.2 communication » 3.2 communication, 2.3 communication, 2.7 communication
a developpement » au developpement, de developpement, le developpement
technology age » technology usage, technology wages, technology a
population per » population panel, population p230, population area
des afrique » en afrique, de l'afrique
per fig » per firm
fig 6.2 » fig 16.2, fig a6.2, figs 6.2
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 age population per fig 6.2 communication costs a developpement des afrique.*.