In fact I have deployed ten sites, only this site is not accessible in my region (China) half of the time, and I have found out the reason, that the site resolves to an ip that is not accessible in my region. so, what is the reason for each site resolving to an ip? Can I change it?
No, but you can certainly see if Support can change it. It’s not likely they will, as it’s often a temporary solution. Use your account’s email address and send to: support AT cloudflare DOT com
Make sure you explain what you just mentioned, and post the ticket number here when you get it.