I also get an error similar warning on thiet ke noi that.It affects keyword rankings?
Cảnh báo: Rating could not be normalized.
Cảnh báo: Rating is empty.
Cảnh báo: This information will not appear as a rich snippet in search results, because it is contained in a hidden HTML element. Except in special circumstances, Google won't display content that is not visible to the user. You should mark up the text that actually appears to your users when they visit your web pages.