I would say the Chinese sinovac vaccine does not work well against the Delta variant, and it does not work well until after the second dose. That is the main one they are using. That is no coincidence. I would also say that 10 deaths out of 26,000 cases means the vaccine is preventing serious illness.
They used the Sinovac vaccine in the past, but it doesn't count anymore. Their count is based on the Pfizer and Moderna vaccinations. Yes they appear to largely prevent serious illness, but recall the issue at hand : virus spread in a highly immunized population.