Perhaps you should try some spelling variations:
technological changes » technological change, technological advances
changes population » change population, changing population, china's population
1.3 communication » 2.3 communication, 13 communication, 4.3 communication
developpement de » developpement des, developpement durable
4 developpement » de developpement, le developpement, et developpement
de afrique » de l'afrique, en afrique, l afrique
care 1.3 » care 13.3, care 14.3, care 5.3
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: technological changes population _ care 1.3 communication costs 4 developpement de afrique.*.