  Recently Dasheng Wei proved that the Brauer-Manin obstruction is the only
obstruction to the Hasse principle for 0-cycles of degree 1 on some fibrations
over the projective line defined by bi-cyclic normic equations. In the present
paper, we prove the exactness of the global-to-local sequence for Chow groups
of 0-cycles of such varieties, which signifies that the Brauer-Manin
obstruction is also the only obstruction to weak approximation for 0-cycles of
arbitrary degree. Our main theorem also generalizes several existing results.
