Google announced from the 1st of August they will stop showing any pages from their supplemental result.
From last week I was constantly monitor on Google site index result and I was amazed that now Google don’t show result from that extended database. I checked number of websites and search for thousand results but I was unable to find any pages under supplement results, so Google take off results from their extended database.
Then I started to digging around Official Google Webmaster Central Blog and there they have clearly mentioned from 31st of July they would stop labeling supplemental result in SERP. Matt (Google Software Engineer) clearly mentioned in his video that many people asked him about site: sitename.com and supplemental results that index in SERP by Google, Matt told don’t worry about supplemental result as Google going to change their algorithm to make search results more specific and accurate, also told that there are at least two changes in Google infrastructure first is deliberately trying to make search result more accurate and second is to change infrastructure to improve quality but as a site benefit it counts result from the site more accurately when it involved in supplemental results.
I think this is enough to understand, if have any other question please leave a comment to discuss this issue in further detail.