I am a Malaysian citizen wish to visit China on coming vacation. How do I apply visa in Doha?

You need to prepare the below documents,
(1) An original copy of your passport with enough blank visa pages, valid for at least another 6 months.
(2) A fully completed copy of Visa Application Form signed by you;
(3) One recent 2×2(in.)-sized color passport photo, white in background, with a full front view of the applicant's head and shoulders but without any head cover.
(4) Qatar Work permit and its photocopy
(5) sometimes, the visa officer will requires the round-trip air ticket

After you prepare all the documents, you need to go to China embassy in Doha to submit the application or entrust a third party to do it on your behalf.

It takes 4 working days for visa processing.