Am I allowed to tell you what I think ?
Ah what the hell...
Foreign candidates do not have more problems getting hired in London. I've had British born managers complain to me about some of the British courses and asking to see more Russians, French and Chinese.
But Chinese candidates are the hardest to place, more than any other group. That's true in every City where we operate, USA, Britain, Japan, anywhere at all.
Many Chinese people speak English at least as well as I do.
However they are undermined by the depressing % who after 1 or even 5 years education in the US or UK are beyond my ability to understand. I'm good with accented English, with all due modesty, I'm excellent, but still fail.
I'm actively trying to find good people, it's what I do. That's the opposite mind set of a hiring manager, who is trying to filter out people from the vast horde who want him to employ them.
Here's a simple free objective test to whether you can speak English.
Ring up some firm which has an outsourced call centre, preferably in India.
Try to spell your address to them. If they ask you to repeat the letters more than 5 times you don't speak English.