Getting Out of Google Supplemental Results
Getting out of the Google Supplemental Results may be possible by improving your website navigation system. To get more pages fully Google indexed, the prominence of important website pages can often be boosted by linking to them from pages within your domain having the highest Page Rank, such as your homepage. The reason for this being that Page Rank is passed from one page to another by links and the most common cause of Supplemental results is lack of Page Rank.
Start by determining your most important web pages which have been made supplemental - for example those promoting lucrative products and services, and then improve your website internal linking by adding links to these pages from more prominent fully Google indexed pages of your site including your homepage. At the same time, ensure that your website navigation system is search engine friendly using a website link analyser.