4 letter words:
fabs9,
fobs9,
fubs9,
oafs7,
sofa7,
abas6,
abos6,
baas6,
boas6,
obas6,
soba6,
suba6,
3 letter words:
fab8,
fob8,
fub8,
fas6,
fou6,
oaf6,
aba5,
abo5,
abs5,
baa5,
bas5,
boa5,
bos5,
bus5,
oba5,
sab5,
sob5,
sub5,
aas3,
sau3,
sou3,
2 letter words:
fa5,
of5,
ab4,
ba4,
bo4,
aa2,
as2,
os2,
so2,
us2,