id	keyword
ger-67	countries
ger-67	efficiency
ger-67	oic
ger-67	education
ger-67	oic countries
ger-67	drs
ger-67	vrs
ger-67	scale
ger-67	crs
ger-67	income
ger-67	timss
ger-67	table
ger-67	percent
ger-67	science