5 letter words:
doubt8,
outdo6,
4 letter words:
boko10,
book10,
bouk10,
kobo10,
dook9,
douk9,
kudo9,
koto8,
toko8,
took8,
touk8,
budo7,
doob7,
boot6,
bout6,
dout5,
3 letter words:
bok9,
kob9,
ouk7,
bod6,
bud6,
dob6,
dub6,
boo5,
bot5,
but5,
obo5,
tub5,
doo4,
dot4,
duo4,
oud4,
tod4,
udo4,
oot3,
out3,
too3,
2 letter words:
ko6,
bo4,
ob4,
do3,
od3,
oo2,
ou2,
to2,
ut2,