  We perform a systematic study of $B\bar{B}^*$, $B^*\bar{B}^*$, $D\bar{D}^*$
and $D^*\bar{D}^*$ systems by using effective interaction in our chiral quark
model. Our results show that the interactions of $B\bar{B}^*$, $B^*\bar{B}^*$,
$D\bar{D}^*$ and $D^*\bar{D}^*$ states are attractive, which consequently
result in $B\bar{B}^*$, $B^*\bar{B}^*$, $D\bar{D}^*$ and $D^*\bar{D}^*$ bound
states. The recent observed exotic-like hadrons of $Z_b(10610)$ and
$Z_b(10650)$ are, therefore in our approach, interpreted as loosely bound
states of $B\bar{B}^*$ and $B^*\bar{B}^*$, while X(3872) and Y(3940) are
$D\bar{D}^*$ and $D^*\bar{D}^*$ molecule states, respectively.
