Perhaps you should try some spelling variations:
voice communication » voice communications, mobile communication, device communication
technologies based » technologies used, technology based, technologies a
based information » basic information, based innovation, land information
4.1 developing » 3.1 developing, 4 developing, 3.3 developing
developing e » developing _, developing a, developing east
contents 3 » contents 1, contents _, contents i
costs 4.1 » costs 4.2, costs 4.4, costs 4.3
e africa » em africa, de africa, eu africa
3 voice » 3 voices, _ voice, a voice

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

• Adding a wildcard symbol may retrieve word variants: technologies based information contents 3 voice communication costs 4.1 developing e africa.*.