$input(prompt,options,window,title,text)

is from the help file, and i using

$input(Seen system,eq,Search true the data base)

the c switch bring the trash can icon to the input box, somone that know about them all? nq showg a icon of a Question mark, and ni show exclamation icon, any other icons you can get? or do somone know about a site to read about this? cos it's nice to find out about more hidden stuff in mirc, i cant find anything about this in mirc.hlp.

Did you read the help file? Because n, q, i and n are definitely mentioned there.
The c-option is not listed though.

You could just cycle the entire alphabet.

Where does the help file tell you that you can change the icon with nq,ni,nc ? i cant find it.

It is not a combination of n and q/i/c. The n-option defines "yes no cancel buttons" and is a separate option. The options i, q, w, and h show icons.
q defines "question"
i defines "info"
c (apparently) defines "recycle"

There's also t, which displays a star icon.

if you like finding hidden stuff in mIRC, have a look at a help file i wrote here which documents all the previously undocumented stuff in mIRC:

http://forum.swiftirc.net/viewtopic.php?f=57&t=16859