联络

to get in touch with / to contact / to stay in contact (with) / liaison / (math.) connection

to ally / to unite / to join / (poetry) antithetical couplet

small net

net-like object / to hold sth in place with a net / to wind / to twist / (TCM) channels in the human body

liaison officer

Liaison Office of the Central People's Government in the Hong Kong Special Administrative Region

contact book

CCP central committee's external affairs department (i.e. Chinese communist party's foreign office)