  It has been showed that two entangle pure states can violate the bilocal
inequality in the entanglement-swapping network, vice versa. What happens for
mixed states? Whether or not are there separable mixed states violating the
bilocal inequality? In the work, we devote to finding the mixed Werner states
which violate the bilocal inequality by Particle Swarm Optimization (PSO)
algorithms. Finally, we shows that there are pairs of states, where one is
separable and the other is entangled, can violate the bilocal inequality.
