[user1635]

Your site may contain the exact keyphrase e.g 'red, white and blue' exactly as it is, so when you type it in with speech marks your site comes up top because you're looking for the exact phrase. But when you type in 'red white and blue' without the speech marks google sees it as three keywords (red, white, blue), not a set phrase. So results are returned for the most relevant page containing all three keywords. I hope that makes sense.

So now it comes down to wide range of factors to rank all of the pages that contain all three keywords, including on page seo, site trust, inbound links and anchor text etc.

Hope that explains it