how make a bot who say a diffent answer for some triggers words
you can write an unlimitted words trigger and ansawer
use a ini file, in this case a texts.ini seems good :p

you can also do

ON :TEXT::#: {
if (hello* iswm $1-) {
var %m = .msg $chan | goto $+(M,$rand(1,3))
:M1 | %m Yo $nick | return
:M2 | %m Heyya boyya $nick | return
:M3 | %m suup.... $nick | return
}
}

but it's not a proper job :/
so, just follow the exemple below

I hope you'll write really funny answer :D

;for make it properly put space between the if elseif elseif
;that need to be clean :p

;this line* = no more than 5 answers in 30 seconds since the first answer :p
;you can adjust aswell

;* inc -u30 %flood.text | if (%flood.text > 5) { return }

ON *:TEXT:*:#: {

  inc -u30 %flood.text | if (%flood.text > 5) { return }

  if (hello* iswm $1-) {
    var %topic = hello
    .msg $chan $readini(texts.ini,%topic,$r(1,$ini(texts.ini,%topic,0)))
  }

  elseif (* cool * iswm $1-) {
    var %topic = cool
    .msg $chan $readini(texts.ini,%topic,$r(1,$ini(texts.ini,%topic,0)))
  }

  elseif (* bye * iswm $1-) {
    var %topic = bye
    .msg $chan $readini(texts.ini,%topic,$r(1,$ini(texts.ini,%topic,0)))
  }

  elseif (* later * iswm $1-) {
    var %topic = later
    .msg $chan $readini(texts.ini,%topic,$r(1,$ini(texts.ini,%topic,0)))
  }

  elseif (* thank you * iswm $1-) {
    var %topic = thank you
    .msg $chan $readini(texts.ini,%topic,$r(1,$ini(texts.ini,%topic,0)))

  }
}

;and in the texts.ini you'll save in mIRC directory write the answer like this

[hello]
1=Yo $nick
2=Heyya boyya $nick
3=suup.... $nick

[cool]
1=yah way cool
2=I think you're cool also $nick $+ .
3=this is cool

[bye]
1=bya $nick $+ !
2=hasta manana $nick $+ !
3=good day $nick

[later]
1=ttyl $nick
2=see ya ltr $nick
3=ok see ya soon hopefully $nick

[thank you]
1=your welcome:)
2=np $nick 
3=yw $nick

[or more]
1=
2=
3=
4=
5=
etc...