Perhaps you should try some spelling variations:
2.1 communication » 2.14 communication, 2.3 communication, 2.7 communication
urban development » human development
development case » development china
relative some » relative role, relative size, relative income
technology 4 » technology _, technology 1, technology 3
some policy » sme policy, state policy
costs urban » cost urban, across urban, crisis urban
4 relative » _ relative, a relative, 3 relative
policy 2.1 » policy 3.1, policy 1
case a » case 1, case 2, case 3

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

• Adding a wildcard symbol may retrieve word variants: technology 4 relative some policy 2.1 communication costs urban development case a.*.