Psychic mind reading is an ability which is somewhat complementary to psychic telepathy.
Telepathy works with a top-down approach: a degree of communion is achieved, and from there the psychic can observe the larger flows of of thought. Only with a lot of practice can smaller, specific thoughts be discerned.
Psychic mind reading works with a bottom-up approach: the psychic mind reader looks at the reflections the mind creates, and from these reflections deduces and extrapolates the thoughts the observed person has.
In other words, psychic telepathy is a more subjective and spiritual approach, while psychic mind reading is a more objective and rational approach. Because of this, psychic mind reading has its roots in psychology and scientific observation.
However, because of the sheer volume of small observations which are necessary for process, the psychic mind reader cannot rely only on the conscious side of his or her mind, but also has to directly engage the subconscious.