Perhaps you should try some spelling variations:
1.4 communication » 5.4 communication, 1.1 communication, 1.3 communication
clean development » human development, urban development
technologies 4 » technologies _
4 information » 2 information, 1 information
china africa » cpia africa, china asia
costs clean » costs clear
3.2 2 » 3.2 _, 3.2 a, 3.2 k
2 1.4 » 2 10.4, 2 11.4, _ 1.4

You may be able to get more results by adjusting your search query.

• Adding a wildcard symbol may retrieve word variants: technologies 4 information 3.2 2 1.4 communication costs clean development china africa.*.