  Vacuum structure, one-particle excitations' spectra and bound states of these
excitations are studied in frame of non-relativistic quantum field model with
current $\times$ current type interaction. Hidden symmetry of the model is
found. It could be broken or exact depending on the coupling constant value.
The effect of "piercing" vacuum , generating the appearance of heavy fermionic
excitations, could occur in the spontaneously broken phase.
