When a site’s traffic from Google search engine dropped significantly or new site with a new domain has no traffic at all from Google search engine, you can expect that your site is no longer appear in Google’s search results.
To ensure that your site is really not index by Google search engine bot, you can do a quick search in Google search by performing a Google site search for its entire URL. A search for [ site:www.snippeit.com ], for instance, returns the following results:
If get no entries from the search result, your site may have been removed from Google index. There are several reasons that your site will be removed from Google’s index such as your site may content hidden text or hidden links, duplicate content, misleading or repeated words, page does not match Google’s description, cloaked page, deceptive redirects, doorway pages, duplicate site or pages and etc. Google has a list of guidelines for website owner. If you want your website to be included in Google index, you will need to following the Google’s Webmaster Guidelines.
After you have make sure your site is conformed to Google’s Webmaster Guidelines, you can submit a request reconsideration for your site by logging in into Google Webmaster Tools. If you haven’t registered with Google Webmaster Tools, you will need to register an Google Account and add your site to Google Webmaster Tools.
In Google Webmaster Tools’ dashboard, click request reconsideration on your right. Select the site that you want to request for reconsideration and the action that you have done to meet Google’s Webmaster Guildelines. After the submission, it may take few weeks to review your website.
Google has a video on this matter that explain why a site may not be appearing in search results and how to get it reconsidered.