body LW_WORDLIST_15P
/(?:\b(?!(?:from|that|have|this|were|with)\b)[a-z]{4,12}\s+){15}/
describe LW_WORDLIST_15P string of 15+ random words
score LW_WORDLIST_15P 5
Ignoring the blogspot comments, something along the lines of the above rule
will catch this sort of stuff. It looks like there are only 13 random words
in your case, so you would need to cut the number of words down, and the
score down.
Some of Jennifer's rules would also catch this sort of thing, but I don't
recall which rules. She had some that checked for unusual letter sequences
that can't happen in English. That doesn't help if your main mail is
Slovak, but if it is English it might be useful.
Loren