Welcome to one of the limitations of mIRC.
Normally mIRC only gives you once space between words, unless you have a scripted variable or alias that adds those spaces in for you.
I use $str($chr(160),N) to generate extra spaces in my scripts, where N is the number of spaces needed.
Example:
msg $chan $str($chr(160),4) hi there
is
<Gomp> hi there
(four spaces)
Hope that was of some help to you gomp.