Discrete Breather (DB) is oscillation mode with spatially localized energy. It is observed in crystals with nonlinear interactions. We search for the numerical solution of DB as a periodic orbit in the phese space using a method combining molecular dynamics and Newton method. We successfully find DBs with various frequencies which are out of the frequency range of the phonon mode. A perturbation solution that makes DB unstable is obtained by stability analysis of standing DB. A solution that keeps the propagating velocity longer is obtained by the modified method for searching propagating DB. DB loses its energy out of oscillation direction, and as a result, stops propagating.