We consider a two parametric family of the planar systems with the form $dot{x}=P(x,;y)+{in}_1p_1(x,;y)+{in}_2p_2(x,;y)$, $dot{y}=Q(x,;y)+{in}_1p_1(x,;y)+{in}_2p_2(x,;y)$, where the unperturbed equation(${in}_1={in}_2=0$) is assumed to have at least one periodic solution or limit cycle. Our aim here is to study the behavior of the system under two parametric perturbations; in fact, using the Poincare-Andronov technique, we impose conditions on the system which guarantee persistence of the periodic trajectories. At the end, we apply the result on the Van der Pol equation ; where, we consider the effect of nonlinear damping on the equation. Also the Hopf bifurcation for the Van der Pol equation will be investigated.