You can use * for the matchtext and then check with $istok (btw your events are missing the location parameter):

Code:
on *:text:*:#:{
if ($istok(hello@hi@are you there?@hi bot@hello bot,$1-,64)) msg $chan hello
}


Or you can use regular expression, which will make the code look more like what you proposed, but I don't recommend using regular expression if you don't understand them, it could easily lead to troubles (for example, the '?' had to be escaped because it would be interpreted otherwise):

Code:
on $*:text:/^(hello|hi|are you there\?|hi bot|hello bot)$/:#:{
msg $chan
}

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