This phase II trial is studying how well giving bevacizumab together with erlotinib works in treating patients with advanced liver cancer. Monoclonal antibodies, such as bevacizumab, can block tumor growth in different ways. Some block the ability of tumor cells to grow and spread. Others find tumor cells and help kill them or carry tumor-killing substances to them. Erlotinib may stop the growth of tumor cells by blocking some of the enzymes needed for cell growth. Bevacizumab and erlotinib may also stop the growth of tumor cells by blocking blood flow to the tumor. Giving bevacizumab together with erlotinib may kill more tumor cells