Perhaps you should try some spelling variations:
2.3 communication » 3.2 communication, de communication, 4 communication
developpement de » developpement des, developpement durable
4 developpement » de developpement, le developpement, et developpement
rate rules » trade rules, water rules, wage rules
de afrique » de l'afrique, en afrique, l afrique
rules 2.3 » rules 4.3, rules 2.2, rules 2.4
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 _ inflation rate rules 2.3 communication costs 4 developpement de afrique.*.