Qi deficiency syndrome: due to the lack of healthy qi, the basic function of the body declines, which is a sign of weakness. It is characterized by mental fatigue, humility, facial loss, dizziness and spontaneous sweating, easy to catch a cold, and aggravated after fatigue. Pulse deficiency, pale and fat tongue.

Blood deficiency: it must be the manifestation of deficiency of viscera caused by deficiency of qi and blood. It is characterized by sallow complexion, dull lips and claws, dizziness and palpitation, insomnia and dreaminess, numbness of hands and feet, limb spasm and so on. Thready pulse, pale tongue.

Dialectically speaking, qi is both yang and blood is yin, but the scope of yin and yang is wider. Yin is not just blood, and yang is not just qi, which can reach the yin and yang of a certain viscera. Yin-yang theory is the yardstick of TCM syndrome differentiation and treatment. There are many traditional things in its existence, which need us to inherit and carry forward and also need to be improved.