Perhaps you should try some spelling variations:
mobile communications » mobile communication
communications costs » communication costs, communications _
development matters » development patterns, development partners, development centers
model development » local development, social development, global development
study relation » study regulation, study selection, study iteration
matters data » patterns data, managers data, matters a
relation co » relations co, relation c, relation von
costs model » cost model, cost models, costs money
das mobile » does mobile, a mobile
co das » so das

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

• Adding a wildcard symbol may retrieve word variants: technology study relation co das mobile communications costs model development matters data.*.