6 letter words:
bookoo12,
4 letter words:
book10,
kobo10,
koto8,
tiki8,
took8,
foot7,
boot6,
obit6,
3 letter words:
kif10,
kob9,
fib8,
fob8,
kit7,
koi7,
fit6,
oft6,
bio5,
bit5,
boo5,
bot5,
obi5,
oot3,
too3,
2 letter words:
ki6,
if5,
of5,
bi4,
bo4,
it2,
oi2,
ti2,
to2,