 This randomized phase II trial is comparing three different combination chemotherapy regimens to see how well they work in treating patients with relapsed or refractory acute myeloid leukemia. Drugs used in chemotherapy work in different ways to stop the growth of cancer cells, either by killing the cells or by stopping them from dividing. Giving more than one drug combination chemotherapy may kill more cancer cells. It is not yet known which combination chemotherapy regimen is more effective in treating patients with relapsed or refractory acute myeloid leukemia. 