  We have used the IRAM 30-m telescope to map some targets with HCO$^+$ (1-0)
and H$^{13}$CO$^+$ (1-0) lines in order to search for gas infall evidence in
the clumps. In this paper, we report the mapping results for 13 targets. All of
these targets show HCO$^+$ emissions, while H$^{13}$CO$^+$ emissions are
observed in ten of them. The HCO$^+$ integrated intensity maps of ten targets
show clear clumpy structures, and nine targets show clumpy structures in the
H$^{13}$CO$^+$ maps. Using the RADEX radiative transfer code, we estimate the
column density of H$^{13}$CO$^+$, and determine the abundance ratio
[H$^{13}$CO$^+$]/[H$_2$] to be approximately 10$^{-12}$ to 10$^{-10}$. Based on
the asymmetry of the HCO$^+$ line profiles, we identify 11 targets show blue
profiles, while six clumps have global infall evidence. We use the RATRAN and
two-layer models to fit the HCO$^+$ line profiles of these infall sources, and
analyze their spatial distribution of the infall velocity. The average infall
velocities estimated by these two models are 0.24 -- 1.85 km s$^{-1}$ and 0.28
-- 1.45 km s$^{-1}$, respectively. The mass infall rate ranges from
approximately 10$^{-5}$ to 10$^{-2}$ M$_{\odot}$ yr$^{-1}$, which suggests that
intermediate- or high-mass stars may be forming in the target regions.
