4 letter words:
boko10,
book10,
bouk10,
kobo10,
pook10,
pouk10,
dook9,
douk9,
kudo9,
budo7,
doob7,
doup7,
pood7,
updo7,
3 letter words:
bok9,
kob9,
kop9,
bop7,
ouk7,
pub7,
bod6,
bud6,
dob6,
dop6,
dub6,
dup6,
pod6,
pud6,
boo5,
obo5,
oop5,
oup5,
poo5,
upo5,
doo4,
duo4,
oud4,
udo4,
2 letter words:
ko6,
bo4,
ob4,
op4,
po4,
up4,
do3,
od3,
oo2,
ou2,