I have been learning from Mrs. Amit Yaghoubi's lectures about tefilah from Torah Anytime. I find her explanations amazing and I hope you will too. She started a series on the various depths of tefilah and how we can tap into them in order to upgrade our prayers to Hashem from second-grade level. In addition, her current uploaded lecture on Miriam and Pesach is just as amazing.
Go here to start learning. Her lectures are for women only.
