The Elemental Emotions cards are associated to the Chinese Five Elements and the Microcosmic Orbit (Governing and Conception Vessels). Without deep-diving into the theory, having a basic understanding of key elements will help you when reading the cards. Not to be used as a diagnostic tool for reading the body, but as a way to understand the energy of the emotions and how they may be affecting the body.
This PDF is a simple way for you to start reading the cards for yourself and others.