Perhaps you should try some spelling variations:
voice communication » voice communications, mobile communication, device communication
developpement en » developpement et, developpement des, developpement de
typologie cices » typologie eines, typologie des
cices variation » price variation, die variation, does variation
a voice » _ voice
a des » a der, a das
a de » a die, a der, _ de

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

• The words AND, OR and NOT may confuse the search; try adding quotes: "typologie cices variation _ a voice communication ((a de) OR (a des)) developpement en afrique.~".
• Adding a wildcard symbol may retrieve word variants: typologie cices variation _ a voice communication ((a de) OR (a des)) developpement en afrique.*.