zhfa hzfa zfha fzha hfza fhza zhaf hzaf zahf azhf hazf ahzf zfah fzah zafh azfh fazh afzh hfaz fhaz hafz ahfz fahz afhz
Note: these 'words' (valid or invalid) are all the permutations of the word zhfa. These words are obtained by scrambling the letters in zhfa.