flows lfows folws oflws lofws olfws flwos lfwos fwlos wflos lwfos wlfos fowls ofwls fwols wfols owfls wofls lowfs olwfs lwofs wlofs owlfs wolfs flosw lfosw folsw oflsw lofsw olfsw flsow lfsow fslow sflow lsfow slfow foslw ofslw fsolw sfolw osflw soflw losfw olsfw lsofw slofw oslfw solfw flwso lfwso fwlso wflso lwfso wlfso flswo lfswo fslwo sflwo lsfwo slfwo fwslo wfslo fswlo sfwlo wsflo swflo lwsfo wlsfo lswfo slwfo wslfo swlfo fowsl ofwsl fwosl wfosl owfsl wofsl foswl ofswl fsowl sfowl osfwl sofwl fwsol wfsol fswol sfwol wsfol swfol owsfl wosfl oswfl sowfl wsofl swofl lowsf olwsf lwosf wlosf owlsf wolsf loswf olswf lsowf slowf oslwf solwf lwsof wlsof lswof slwof wslof swlof owslf woslf oswlf sowlf wsolf swolf
Note: these 'words' (valid or invalid) are all the permutations of the word flows. These words are obtained by scrambling the letters in flows.