Perhaps you should try some spelling variations:
technologien series » technologies series, technology series, technologies varies
information centers » information contents, information officers
series information » business information
communication cost » communication costs, communication costa, communications costs
de communication » mobile communication, online communication
11.3 developing » 1.3 developing, 10.3 developing, 11.5 developing
centers 3rs » centers 3, centers 3.3, centers 3.8
cost 11.3 » cost 11.5, cost 4.1.3, costs 11.1

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

• Adding a wildcard symbol may retrieve word variants: technologien series information centers 3rs de communication cost 11.3 developing _ africa.*.