  We search for the singly Cabibbo-suppressed decay $D^+ \to K^- K^0_s \pi^+
\pi^+ \pi^0$ using the full data set of 988 fb$^{-1}$ recorded by the Belle
experiment at the KEKB $e^+e^-$ collider. We measure the branching fraction for
this decay to be $\left({6.4^{+3.9}_{-3.8}}\right)\times10^{-5}$ with an upper
limit at 95% credibility of $1.4\times10^{-4}$. We also measure the sum of the
branching fractions for $D^+ \to \bar{K}^* \eta \pi^+$ and $D^+ \to \bar{K}^*
\omega \pi^+$ to be $\left({6.0^{+6.3}_{-5.8}}\right) \times {10^{-5}}$ with an
upper limit at 95% credibility of $1.8\times10^{-4}$.
