Here's what rhymes with tumbaku.
coup qu ku coo cou gu goo to who you do two new too due knew du grew que u crew pursue q shoe zu anew clue cue dew glue lieu queue shew su sue tu vous accrue chew cu deux fu lu rue taboo zoo adieu ado bu hu ju jus loo mu nu peu pu seu shu sou tattoo vu woo yew yu beaucoup boo chou chu doo ewe feu ru shou thu tue vou wou wu clew moo pooh poo shoo gnu roux thew whew achoo through few true view blue drew threw blew flew screw bamboo canoe hue undue flue slew stew undo untrue brew flu jusqu pew piu skew thru fue hew mieux shrew tzu vue askew mew foreknew kazoo slue phew wazoo booboo regrew into interview avenue renew debut ensue rendezvous retinue subdue overdue barbecue eschew outdo shampoo sprue vnto imbue outgrew overdo redo strew cockatoo halloo spew valuer barbeque bugaboo endue zebu indue marabou peekaboo buckaroo muumuu overshoe superglue overgrew atishoo review revenue hitherto overview residue caribou construe overthrew kangaroo revue sinew ballyhoo honeydew hullabaloo fondue bestrew overflew prevue overdrew withdrew misconstrue