  Motivated by the large rates of $B\rightarrow (\chi_{c0}, \chi_{c2}, h_c)K$
decays observed by the $BABAR$ and Belle collaborations, we investigate the
nonfactorizable contributions to these factorization-forbidden decays, which
can occur through a gluon exchange between the $c\bar c$ system and the
spectator quark. Our numerical results demonstrate that the spectator
contributions are capable of producing a large branching ratio consistent with
the experiments. As a by-product, we also study the Cabibbo-suppressed decays,
such as $B\rightarrow (\chi_{c0}, \chi_{c2}, h_c)\pi$ and the U-spin-related
$B_s$ decay, which have so far received less theoretical and experimental
attention. The calculated branching ratios reach the order of $10^{-6}$, which
in within the scope of the Belle-II and LHCb experiments. Further, the
$CP$-asymmetry parameters are also calculated for these decays. The obtained
results are compared with the available experimental data and numbers from
other predictions. We also investigate the sources of theoretical uncertainties
in our calculation.
