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