Hope this helped

Code:
on *:text:*:#: {
  var %logchat = word1,word2,word3,word4
  var %a = 1
  while ($gettok(%logchat,%a,44)) {
    var %logword = $v1
    if (%logword isin $1-) { 
      var %nolog = $true 
      break
    }
    inc %a
  }
  if (%nolog) { return }
  else { write chatlog.txt $1- }
}