Doleful means very sad — the heavy kind you can see on a face or hear in a voice, not a small “I’m a bit sad.” A doleful look, a doleful cry, a doleful song: the word likes to sit in front of a thing you can notice. It sounds a little old and bookish; in everyday talk people more often say sad, miserable, or gloomy. It does not mean “on the dole” (British informal for living on unemployment money). That dole is a different word that only looks the same.