For example, this is the description of my blog located header, just below the blog title.

Here is the screenshot of the problem on sharing links on Facebook. Using previous post from my blog.

Notice the problem not fetching data from the content? But how it should normally be is the following.

I have no idea why it works like this on Blogger blogs. However, there’s one simple solution (or you’d probably need to edit templates). Under Settings menu on back-end, do not type anything for Description. If you want to add blog descriptions somewhere, use Blogger widgets.