Perhaps you should try some spelling variations:
clean development » human development, urban development
de communication » mobile communication, online communication
technology 3.1 » technology 1, technology 2.2, technology _
3.1 relation » 4.1 relation, 3.1 regulation, 2.3.1 relation
relation re » relation de, relational re, relation des
costs clean » costs clear
re crisis » pre crisis, de crisis, care crisis
crisis de » crisis del, crisis due, crisis debt
a aortic » _ aortic, _ artic

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

• Adding a wildcard symbol may retrieve word variants: technology 3.1 relation re crisis de communication costs clean development a aortic.*.