"Foreign" here means "Western" or "American", I suppose. As far as I know, Yandex isn't blocked in China, and they are Russian, so foreign to China. I don't know their market share (they fall under "other", but so does "bing" often), still worth a mention maybe.
Can confirm that Bing is blocked in China for me. Having lived in China for the past decade, I've found that increasingly, my VPN has gone from sporadically on to sporadically off. China's internet has become an entity unto itself, divorced from the rest of the world.
<a href="https://cn.bing.com/" rel="nofollow">https://cn.bing.com/</a> IS WORKING. Testing from Shanghai without VPN.<p>bing.com is not working.