My travel guide blog has problem in Google indexing. It used to have 800 pages indexed at Google, but now it only has 160. I think the reason of this is because Google thinks I have internal duplicate content on my blog. I notice that my tag pages does not indexe well now. Probably Google thinks they have almost similar content between two pages. For example http://etravelogy.com/tag/music-boxes/ and http://etravelogy.com/tag/official-languages-of-switzerland/. The only different thing in those pages is the title tag. So I definately need to change the tag page so Google thinks it has different pages. Probably adding amazon product based on the tag keyword.