A randomized, double-blind, controlled trial for Bu-Fei-Huo-Xue Capsule in the treatment of novel coronavirus pneumonia (COVID-19) convalescence patient with ''Fei-Pi-Qi-Xu zhen''

INTERVENTION: Control:conventional therapy;Experimental group:Bufei Huoxue Capsule, 1.4g/day, three times a day, three months of treatment; CONDITION: Novel Coronavirus Pneumonia (COVID‐19) PRIMARY OUTCOME: St George's respiratory questionnaire score;Fatigue assessment scale;Six minute walking experiment; INCLUSION CRITERIA: 1. Aged >=18 years; 2. according to the new diagnostic protocol for coronavirus pneumonia (trial version 7), the new type of coronavirus pneumonia is diagnosed; 3. after treatment, the disease reaches the discharge standard specified in the new coronavirus pneumonia diagnosis and treatment plan (trial version 7); 4. the disease is in recovery stage, according to the new coronavirus pneumonia. Diagnosis and treatment plan (trial version 7) diagnosis standard of TCM syndrome differentiation is deficiency of lung qi and spleen qi; 5. volunteer to participate in the study and sign the informed consent.