Perhaps you should try some spelling variations:
des developpements » deux developpements, de developpement, et developpements
data communication » data communications
developpements en » developpement en, developpement et, developpements de
der variation » de variation, does variation, die variation
apology der » apology mea, apologien der, apologie des
6 user » _ user, 3 user, 4 user
a user » 3 user, a user's
a des » a der, a das

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: "apology der variation ((6 user) OR (a user)) data communication a des developpements en afrique.~".
• Adding a wildcard symbol may retrieve word variants: apology der variation ((6 user) OR (a user)) data communication a des developpements en afrique.*.