www.google.co.th normally uses encryption to protect your information. When Baidu Browser tried to connect to www.google.co.th this time, the website sent back unusual and incorrect credentials. Either an attacker is trying to pretend to be www.google.co.th, or a Wi-Fi sign-in screen has interrupted the connection. Your information is still secure because Baidu Browser stopped the connection before any data was exchanged.
You cannot visit www.google.co.th right now because the website uses HSTS. Network errors and attacks are usually temporary, so this page will probably work later.