This phase II trial studies how well giving sunitinib malate together with capecitabine works in treating patients with unresectable or metastatic liver cancer. Sunitinib malate may stop the growth of tumor cells by blocking some of the enzymes needed for cell growth and by blocking blood flow to the tumor. Drugs used in chemotherapy, such as capecitabine, work in different ways to stop the growth of tumor cells, either by killing the cells or by stopping them from dividing. Giving sunitinib malate together with capecitabine may kill more tumor cells