5 letter words:
brook11,
robot7,
rotor5,
4 letter words:
book10,
bork10,
kobo10,
boob8,
koto8,
rook8,
took8,
boor6,
boot6,
bort6,
broo6,
root4,
roto4,
toro4,
torr4,
3 letter words:
kob9,
bob7,
kor7,
boo5,
bot5,
bro5,
brr5,
orb5,
rob5,
oot3,
ort3,
rot3,
too3,
tor3,
2 letter words:
bo4,
or2,
to2,