Perhaps you should try some spelling variations:
oral communication » personal communication
information case » information based, information can, information costs
technologies 4 » technologies _
3.3 developing » 4 developing, 2 developing, 1 developing
4 information » 2 information, 1 information
costs 3.3 » costs 2.3, costs 3.5, costs 4.3
case u.s » case 4.1, case 4.2, case 2.3
u.s oral » u.s oil

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

• Adding a wildcard symbol may retrieve word variants: technologies 4 information case u.s oral communication costs 3.3 developing _ access.*.