This is a Phase Ib/II clinical study aimed at exploring the safety and efficacy of Regimen A (GFH375 in combination with Cetuximab) and Regimen B (GFH375 in combination with AG) in participants with solid tumors.Phase Ib: To evaluate the safety/tolerability and pharmacokinetic (PK) characteristics of GFH375 in combination with cetuximab or AG in participants with solid tumors, and to explore the efficacy of the combination therapy. Phase II: To evaluate the efficacy, safety/tolerability and PK characteristics of the combination therapy, and to explore the correlation between bio-marker and clinical efficacy.