id	keyword
cana-4745	research
cana-4745	genglubu
cana-4745	analysis
cana-4745	china
cana-4745	south
cana-4745	hainan
cana-4745	cluster
cana-4745	maritime
cana-4745	keyword
cana-4745	heritage
cana-4745	studies
cana-4745	field
cana-4745	network