  We study the indication of large different branching ratios between $B^{-}\to
D^{(*)0} K^{-} {K}^{0}$ and $\bar{B}_{d}\to D^{(*)+} K^{-} {K}^{0}$ observed by
Belle. Interestingly, the same situation is not found in the decays $B\to
D^{(*)} K^{-} {K}^{*0}$. If there exist no intermediate resonances in the
decays $B^{-}\to D^{(*)0} K^{-} {K}^{0}$, a puzzle will be arisen. We find that
the color-suppressed processes $B^{-}\to D^{(*)0}a^{-}_{0}(1450)$ with
$a^{-}_{0}(1450)\to K^{-} {K}^{0}$ could be one of the candidates to enhance
the BRs of $B^{-}\to D^{(*)0} K^{-} {K}^{0}$. Our conjecture can be examined by
the Dalitz plot technique and the analysis of angular dependence on $K^{-}
{K}^{0}$ state at $B$ factories.
