Question About SERP Google

I search my site on google with syntax like this - site:example.com

And I got this message :

In order to show you the most relevant results, we have omitted some entries very similar to the 1 already displayed.
If you like, you can repeat the search with the omitted results included.

Click to expand...

If I click "repeat the search with the omitted results included."
I get about 129 results

I get 36 backlink from yahoo site explorer.

What my website into the sandbox?

This does not mean sandboxed, message is likely because of duplicate content / same titles / close to duplicate content

As well, sandbox does not mean deindexed, sandboxed means buried in the SERP results for the term you're trying to rank for

It's actually the reverse of what your thinking. You haven't been sandboxed, the comment is letting you know that many of your pages are indexed. When displaying the SERP there isn't any reason to show every indexed page from a relevant site.

You see the reults of this many times when you're doing regular searchs. Especially authority sites like Wikipedia. There will be one main listing for a site, and then one or more sublistings directly under it. A lot of times there will also be a link under the sublisting that says more results available so that a visitor can click it to see all the relevant results on your site.

Don't worry about it. It's a good thing.