Perhaps you should try some spelling variations:
actors communication » actions communication, active communication, networks communication
communication 8.2.1 » communication 2.4, communication 3.2, communication 4.1
information center » information centers, information centre, information content
technologies a » technologies _, technologies 4, technologies 2
a information » 2 information, 1 information
20 developing » 2 developing, 10 developing, 24 developing
developing a » developing _
center 2.1 » century 2.1, center 1
2.1 actors » 2.1 factors, 2.2 actors, 4.1 actors
a afrique » l afrique, en afrique
8.2.1 20 » 8.2.1 _, 8.2.1 a, 8.2.1 ad

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

• Adding a wildcard symbol may retrieve word variants: technologies a information center 2.1 actors communication 8.2.1 20 developing a afrique.*.