Knocking rhymes with:
blocking, clocking, cocking, docking, flocking, hocking, locking, mocking, restocking, rocking, shocking, socking, stocking, undocking, unlocking
Knocking sounds like:
kansan's, kansans, kansans', keynesians, knick-knack, knick-knacks, knickknack, knickknacks, kyongsang