Hidden and doubly heavy molecular states from interactions $$D^{(*)}_{(s)}{{\bar{D}}}^{(*)}_{s}$$/$$B^{(*)}_{(s)}{{\bar{B}}}^{(*)}_{s}$$ and $${D}^{(*)}_{(s)}D_{s}^{(*)}$$/$${B}^{(*)}_{(s)}B_{s}^{(*)}$$

In this work, we perform a systematical investigation about the possible hidden and doubly heavy molecular states with open and hidden strangeness from interactions of /, /, /, and / in a quasipotential Bethe-Salpeter equation approach. The interactions of the systems considered are described within the one-boson-exchange model, which includes exchanges of light mesons and meson. Possible molecular states are searched for as poles of scattering amplitudes of the interactions considered. The results suggest that recently observed can be assigned as a molecular state of , which is a partner of state as a molecular state. The calculation also favors the existence of hidden heavy states with spin parity , with , and with , , and . In the doubly heavy sector, the bound states can be found from the interactions with , with , with and , and with and . Some other interactions are also found attractive, but may be not strong enough to produce a bound state. The results in this work are helpful for understanding the , and future experimental search for the new molecular states.