Perhaps you should try some spelling variations:
clean development » human development, urban development
de communication » mobile communication, online communication
development life » development level, development law, development latin
rate placebo » a placebo, race place
life afrique » life africa, l afrique
costs clean » costs clear
placebo de » place de, placebo _, placebo test

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

• Adding a wildcard symbol may retrieve word variants: technology _ inflation rate placebo de communication costs clean development life afrique.*.