Swami Dayananda has clarified the nature and structure of human suffering and well as what is involved in the relative resolution of this suffering. The Vedanta Psychology series concerns itself with this topic alone in practical terms.
Vedanta Paribhasha by Mani Dravid Shastri
Prabodhasudhakara (Kannada) by V Subrahmanian
Panchadashi (Kannada) by V Subrahmanian
Vedanta Psychology by Bede Clifford
Taittiriya Upanishad by Prof Mahadevan B