It's possible for Canadian PR to get 10 year M entry visa to US. normally US embassy/consulates in Canada will give you that, not likely in Beijing.
Also you have to get established in Canada to be possible, such as lived in canada for more than 6 months, have jobs, owning properties.
the fact you were approved Canadian PR does not automatically make you enter US easier. US welcomes Canadian residents( citizens and established residents) to visit, study, do business in US because they are highly unlikely to stay in US illgeally after their visit. but they do not like people use Canadian PR as a bridge to get into US. hope these help.