Perhaps you should try some spelling variations:
population censuses » population census, population densities
communication cost » communication costs, communication costa, communications costs
2.4 communication » 2.14 communication, 5.4 communication, 2.3 communication
censuses prices » consumer prices
developing east » development east, developing a, developing asia
3.3 developing » 4 developing, 2 developing, 1 developing
technology em » technology e, technology eimt, technology e.g
em population » en population, ehc population, 2 population
east afrique » east africa, east african, en afrique
prices 2.4 » prices 4, practices 2.4, services 2.4
cost 3.3 » cost 3.2, cost 2.3, cost 3.4

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

• Adding a wildcard symbol may retrieve word variants: technology em population censuses prices 2.4 communication cost 3.3 developing east afrique.*.