Can I make Views Fast Search NOT search comments?

I'm using views fast search to drill down to very specific types of posts and only to search the posted content - NOT the comments added to each post as they are often irrelevant and muddle results.

Is there any way I can make views_fast_search ignore the comments made to each post?

I'm also having trouble searching on short brand names - like VISA - it will bring up practically every post (43000 posts) in that content type.

Any suggestions?