The indexed links has down

Hi all,

What's happen with my website? In this week, i use google web master tool to check links indexed has down. How could I do?

Thanks
Dinh

 

Do you have duplicate content? Mean 2 or more url with same content.

If so, you might be penalty by google. So index url go down.

 

i also suspect that you may have a duplicate content in your site that's why your index is decreasing.

 

Thanks
I'll check my site for duplicate content and edit it

 

I know this is old but you are better off checking this in Google direct. The webmaster tool is always wrong for me.

 

How often is the sitemap indexed?