I am Canadian Citizen working in Qatar and want to visit

and attend China International Printing Technology Exhibition during the week from May 8th to May 13th and also to do sight seeing.
As I have been working in Qatar and have a probability my work related business trips in other countries during the same time, so I might revise my visit for sight seeing only.
Is this ok if I apply for visa without making a booking for air ticket, as I might need to re-schedule my visit on some other date.
Ejaz