As Dave stated, lacquer almost always requires a clearcoat. If you are getting a milky haze in it, that may be a condition known as "blushing", caused by humidity. Back in the old days when dinosaurs roamed the earth and I worked in autobody, we would wait for the paint to dry, than buff out the haze. If not successful, a repaint was in order. But the clearcoat part... buy a compatible clear.