If you read the CIC police checks section here: http://www.cic.gc.ca/english/information/security/police-cert/index.asp it has information on how to obtain them.
CHINA
Non-Resident Requests
You can obtain a police certificate from the local Public Security Bureau by asking someone to act on your behalf in China. To do this, you must give this person:
•Specific written authorization.
•If you are a Chinese national, a photocopy of your national identification card and household register booklet (hukou).
•If you are a non-Chinese national, a photocopy of your passport, including the page that contains the Chinese visa.
The person acting on your behalf must present the documents to the local Public Security Bureau.
South Korea, Republic of
Do I need to provide a police certificate when applying for permanent residence?
Yes.
How and where do I obtain one?
If you live outside South Korea
You should request a Criminal History Information Record (Bumjoi Gyung-ryuck ·Soosa Gyung-ryuck Jo Hoi Hoibo-seo, 범죄경력 · 수사경력조회 회보서) from a police station in Korea. Immediate family members (parents, spouses, siblings) may request a certificate on your behalf. Please note all police certificates should include all records, including any lapsed records.
Vietnam:
Non-Resident Requests
Applicants should contact the nearest Vietnamese embassy for information

CHINA
Non-Resident Requests
You can obtain a police certificate from the local Public Security Bureau by asking someone to act on your behalf in China. To do this, you must give this person:
•Specific written authorization.
•If you are a Chinese national, a photocopy of your national identification card and household register booklet (hukou).
•If you are a non-Chinese national, a photocopy of your passport, including the page that contains the Chinese visa.
The person acting on your behalf must present the documents to the local Public Security Bureau.
South Korea, Republic of
Do I need to provide a police certificate when applying for permanent residence?
Yes.
How and where do I obtain one?
If you live outside South Korea
You should request a Criminal History Information Record (Bumjoi Gyung-ryuck ·Soosa Gyung-ryuck Jo Hoi Hoibo-seo, 범죄경력 · 수사경력조회 회보서) from a police station in Korea. Immediate family members (parents, spouses, siblings) may request a certificate on your behalf. Please note all police certificates should include all records, including any lapsed records.
Vietnam:
Non-Resident Requests
Applicants should contact the nearest Vietnamese embassy for information