Trouble creating a Regex to filter spam

[yontekh]

I would like to make a regex that filters out messages that

• contain less than 3 words
  • a way to exclude words from this rule, like LOL or Kappa not counting against the 3 word minimum count

I just cannot figure it out...
This could be added as a feature in the menu labeled "reduce spam" or something, but thats up to the devs.