I have a site(example: www.abc.com) and I create a blog under the site (www.abc.com/blog). When I update a articl in blog and I almost can trace it with google search engines immediately, but the url of the search result is www.abc.com/blog but not my site www.abc.com, the articl is used to describe one of products in my site and the title of the articl is the product's name, I also add some url of my site in the articl. Why?? who can answer me, thanks Just the site(www.abc.com) is a example but not my real site.
If you're writing blog posts under the url of abc.com/blog, then that's what the search results are going to show when indexing that blog post
If you setup blogging software under /blog subdirectory, then it's normal. If you want domain/posturl, then move the installation to domain root.
Why not? You can see it from the path of the URL that first starts with your homepage/domain name. And this is one of the best methods you can adopt to promote your main website. All the best!