Perhaps you should try some spelling variations:
voice communication » voice communications, mobile communication, device communication
technologies used » technologies based, technology used, technologies _
used information » user information, use information, based information
information 2.3 » information 12.3, information 1.3, information 2.2
3 developing » 3 development
und voice » one voice
2.3 und » 2.3 un, 2.3 une, 2.3 unit
costs 3 » costs _, costs 4, costs a

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

• Adding a wildcard symbol may retrieve word variants: technologies used information 2.3 und voice communication costs 3 developing _ areas.*.