Perhaps you should try some spelling variations:
communications costs » communication costs, communications _
do communications » 10 communications, 14 communications, 2 communications
infection rates » inflation rates
rates secrets » masters secrets, trade secrets
developing l2 » developing _, developing a, developing e
4 developing » 3 developing
secrets do » secrets _, secrets from
l2 afrique » l afrique, en afrique
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 _ infection rates secrets do communications costs 4 developing l2 afrique.*.