Perhaps you should try some spelling variations:
online kommunikation » online communication, online communications, interne kommunikation
developpement l » developpement il, developpement la, developpement de
farmers online » partners online, farmers convinced, farmers alliance
der variation » de variation, does variation, die variation
typology der » typologie der, typologien der, typologie des
variation a » variation _, variation 6, variation 5
a farmers » a farmer's, _ farmers, 5 farmers
l afrique » en afrique
a set » _ set
a et » a net, a bet, a jet

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: "typology der variation a farmers online kommunikation ((a et) OR (a set)) developpement l afrique.~".
• Adding a wildcard symbol may retrieve word variants: typology der variation a farmers online kommunikation ((a et) OR (a set)) developpement l afrique.*.