Inclusion Criteria:

          -  Signed and dated written informed consent which is approved by IRB/EC, willing and
             able to comply with scheduled treatment, all examinations at study visits, and other
             study procedures.

          -  ECOG PS 0-1.

          -  Have histologically or cytologically confirmed locally advanced or metastatic
             non-squamous NSCLC disease.

          -  Before enrollment, a documented confirmed presence of activating mutations in exon 20
             of the HER2 gene must be provided. Sufficient tumor tissue samples should be provided
             to retrospectively confirm the mutation status of the HER2 gene.

          -  Must have measureable disease per RECIST v1.1.

          -  For advanced NSCLC, patients must have had progressive disease on or after a platinum
             based chemotherapy, with or without immune checkpoint inhibitors (PD-1/PD-L1
             inhibitors) and/or anti-angiogenic drugs. No more than 2 prior lines of systemic
             therapy are allowed.

          -  The laboratory test values must meet the following standards to manifest that the
             functional level of important organs/systems meets the requirements.

          -  Female patient of childbearing potential (WOCBP) and male patient whose - partner is
             WOCBP must agree to use effective contraception method during the study period.

        Exclusion Criteria:

          -  Malignant tumors with other pathological types.

          -  Medical history of other active malignancies within last 5 years.

          -  Subjects with active CNS metastases.

          -  Previously treated with targeted drugs for HER2 gene mutations,or previously treated
             with docetaxel.

          -  Prior to the first dose of study treatment, patients with severe effusions with
             clinical symptoms, severe cardiac disease, or severe infection.

          -  Prior to the first dose of study treatment, patients with diseases or special
             conditions that affect drug administration and absorption.

          -  Congenital or acquired immunodeficiency.

          -  History of allergy to the study drugs or components.

          -  Prior to the first dose of study treatment, or during the study period, patients
             receive or are anticipated to receive continuous strong CYP3A4 inducers or inhibitors,
             P-gp inhibitors, or medications that are known to cause QT/QTc prolongation.