"The essence is empty but the essence is real", which is mostly manifested as "the mixture of reality and reality". What is this?

For example, a person is deficient in qi, which is essentially deficiency.

It is easy to stagnate qi and blood stasis after qi deficiency. Due to qi stagnation and blood stasis, symptoms such as heat depression, fever and blood coagulation are produced, which is the standard.

The symptoms of qi deficiency, qi stagnation and blood stasis are mixed with excess and deficiency. During treatment, we should get rid of depression, heat and other problems, and at the same time, we should replenish qi appropriately.