Perhaps you should try some spelling variations:
device communication » services communication, voice communication, mobile communication
technologien from » technologies from, technology from, technologien fur
formal contexts » formal context, formal contracts, local contexts
4 developing » 3 developing
from formal » from informal
contexts we » context we, contexts new, contexts _
we device » when device, own device, _ device
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: technologien from formal contexts we device communication costs 4 developing _ africa.*.