rukhs urkhs rkuhs kruhs ukrhs kurhs ruhks urhks rhuks hruks uhrks hurks rkhus krhus rhkus hrkus khrus hkrus ukhrs kuhrs uhkrs hukrs khurs hkurs ruksh urksh rkush krush ukrsh kursh ruskh urskh rsukh srukh usrkh surkh rksuh krsuh rskuh srkuh ksruh skruh uksrh kusrh uskrh sukrh ksurh skurh ruhsk urhsk rhusk hrusk uhrsk hursk rushk urshk rsuhk sruhk usrhk surhk rhsuk hrsuk rshuk srhuk hsruk shruk uhsrk husrk ushrk suhrk hsurk shurk rkhsu krhsu rhksu hrksu khrsu hkrsu rkshu krshu rskhu srkhu ksrhu skrhu rhsku hrsku rshku srhku hsrku shrku khsru hksru kshru skhru hskru shkru ukhsr kuhsr uhksr huksr khusr hkusr ukshr kushr uskhr sukhr ksuhr skuhr uhskr huskr ushkr suhkr hsukr shukr khsur hksur kshur skhur hskur shkur
Note: these 'words' (valid or invalid) are all the permutations of the word rukhs. These words are obtained by scrambling the letters in rukhs.