The search engine that China uses is Baidu.
Baidu is often referred to as being "China's Google" and has a dominant market share.
Other popular search engines that are used in China are Shenma for mobile search users, Bing and even Haosou "360 search".
Gmail as well as other Google services are also banned and even blocked in mainland China by the Great Firewall.
Due to Gmail and other Google services being blocked and banned by the Great Firewall they are not accessible without a workaround such as a Virtual Private Network or VPN.
China's ban on Gmail and Google services started in the year 2010, after a dispute over censorship with the Chinese government, which has also continued to restrict access to foreign hosted internet services to control information and also promote domestic alternatives.
China's government censors online content that they deem contrary to it's values and culture, which is a policy that is enforced by the Great Firewall.
And the blockage of Google services including Gmail in China, stems from a disagreement that took place in 2010, when Google had refused to comply with the demands of the Chinese government to censor the search results, which lead to Google moving their operations out of mainland China.
The China ban on Google services including Gmail helps promote and also protect China's own internet services and companies, like Sohu Mail and QQ Mail, by limiting competition from foreign platforms.
To access your Gmail in China you can install a reliable paid VPN service onto your computer and mobile devices before you get to China, as many VPN websites are also blocked within China.
Once the VPN is installed, you can open the VPN app and connect to a serve in a country in which the Gmail is not blocked.