Perhaps you should try some spelling variations:
3.2 communication » 3 communication, 2.3 communication, de communication
developpement de » developpement des, developpement durable
transfer sector » transfer factor, transport sector, transfer factors
4 developpement » de developpement, le developpement, et developpement
sector wage » sector wages
de afrique » de l'afrique, en afrique, l afrique
wage rice » wage price, wage rate, wage hike
rice 3.2 » price 3.2, rice 3.1, rice 3.3
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: technology transfer sector wage rice 3.2 communication costs 4 developpement de afrique.*.