There are 2 options here… go to the Google search bar and type in your search term or phrase and then go from one page to the next and try and find your site. If your site is in the top 10 pages, no big deal. Understand though that if your site is not on the 1st page, the chances of your site being found for that search term is slim to none and slim done left town! If your site isn’t on page 1 and one of the 1st 3 choices, your site probably won’t get many visits either.
The second option is to try this tool:
I have found this tool to be very helpful. Don’t use it too much however, Google is watching you!