Perhaps you should try some spelling variations:
net developpement » et developpement, de developpement, le developpement
developpement de » developpement des, developpement durable
variation des » variation _, variation 6, variation series
a variation » la variation, _ variation, 2 variation
de afrique » de l'afrique, en afrique, l afrique
apology a » apology _, apology mea, typology a
der power » peer power, dc power, d power
den power » down power, when power, dc power
a net » a new, _ net, a neo

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 a variation des ((der power) OR (den power)) communication a net developpement de afrique.~".
• Adding a wildcard symbol may retrieve word variants: apology a variation des ((der power) OR (den power)) communication a net developpement de afrique.*.