The scope of morality definitely includes thoughts, but not in the same way as actions. That’s because many thoughts are involuntary, or at least not voluntary enough, which is a problem when it comes to moral evaluation, or attributing praise or blame. Plus, although the cliche is true that “ideas have consequences,” at another level thoughts are rather inert when compared to actions. The thought of murdering someone, so long as it stays in my head, doesn’t lead to anyone’s death; but the action involves someone actually dying. For these reasons (and others), thoughts have not received as much attention as actions.
But the notion of right or wrong certainly applies to some thoughts. And we can discuss good and bad thoughts, even if we don’t attach praiseworthiness or blameworthiness to them.