hobh ohbh hboh bhoh obhh bohh hohb ohhb hhob hhob ohhb hohb hbho bhho hhbo hhbo bhho hbho obhh bohh ohbh hobh bhoh hboh
Note: these 'words' (valid or invalid) are all the permutations of the word hobh. These words are obtained by scrambling the letters in hobh.