Unknowing rhymes with:
knowing, snowing, bestowing, blowing, boeing, bowing, crowing, easygoing, flowing, foregoing, forgoing, glowing, going, growing, hoeing, knowing, lowing, owing, plateauing, rowing, sewing, showing, slowing, snowing, sowing, throwing, toeing, towing, undergoing
Unknowing sounds like:
unassuming, unceasing, unconscious, uneasiness, uneconomic, unionizing, uniqueness, unisons, unknowns, unsung