There could be hundreds of reasons.. With info that u provided, it looks like your site gone into supplemental.. there is allmost allways a chance to fix everything no...
Thanks for your answers. Would you please tell me what do you mean by going supplemental? There is no other copy of the content on the web (specially the articles I mentioned). Thanks again.
If the pages were in the Supplemental index they would still be listed in webmaster tools. Are you seeing the pages there? Are they dup content?
It seems when I search for all the article pages of my website (using site: inurl most of the articles are there but the content is not indexed or appear in searches. No, the content used to be unique (first time appeared on my website).
Google has encountered an indexing problem which can be read about at: http://blog.ineedhits.com/search-ne...to-index-thousands-of-new-pages-25288693.html I think the problem still exists for many people.