Perhaps you should try some spelling variations:
communication cost » communication costs, communication costa, communications costs
technologies 2.1 » technologies _, technologies 4, technologies a
de communication » mobile communication, online communication
2.1 information » 3.1 information
7.3 developing » 3.3 developing, 1.3 developing, 2.2 developing
developing 1 » developing _, developing a, developing e
contents i » contents 1, contents _, contents list
cost 7.3 » cost 2.3, cost 7.4, cost 11.3
i de » i die, i der, i den

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

• Adding a wildcard symbol may retrieve word variants: technologies 2.1 information contents i de communication cost 7.3 developing 1 africa.*.