emacs: searching only for a variable

["H.S." <hs.samix@gmail.com>]

Hello,

If I search for a text in emacs (CTRL+s), it matches all occurrences of 
the search text. For example, I am trying to search a variable "i" in a 
large block of code. How do I tell emacs to hit only that variable and 
not for every 'i' that may occur in the file? I have tried regexp search 
(SHIFT+CTRL+s for '[^a-z]i[^a-z$]'). It sort of works but perhaps there 
is a shorter and faster way.

Thanks.