This randomized phase II trial studies how well gemcitabine hydrochloride works with or without pazopanib hydrochloride in treating patients with refractory soft tissue sarcoma. Drugs used in chemotherapy, such as gemcitabine hydrochloride, work in different ways to stop the growth of tumor cells, either by killing the cells or by stopping them from dividing. Pazopanib hydrochloride may stop the growth of tumor cells by blocking some of the enzymes needed for cell growth. Pazopanib hydrochloride may also stop the growth of tumor cells by blocking blood flow to the tumor. It is not yet known whether gemcitabine hydrochloride is more effective with or without pazopanib hydrochloride in treating patients with soft tissue sarcoma.