Perhaps you should try some spelling variations:
optical communication » optical communications, optic communication, political communication
communication model » communication media
au developpement » du developpement, de developpement, le developpement
developpement de » developpement des, developpement durable
die integrating » time integrating, die integration, die integrative
technology die » technologie die, technology does, technology 4ir
integrating a » integrating _, integrating human
3.2 optical » 3.2 optimal, 3.3 optical, 8.2 optical
de afrique » de l'afrique, en afrique, l afrique
model au » modele au, model a, model aa
a 3.2 » _ 3.2, a 4.2

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

• Adding a wildcard symbol may retrieve word variants: technology die integrating a 3.2 optical communication model au developpement de afrique.*.