The tracking number has only one purpose.
If the buyer opens a Dispute claiming that the parcel has not arrived, the seller can use the tracking number to prove that it actually has been received.
In most cases, 'tracking' is actually Confirmation of Delivery, which means that the item has been delivered. It might possibly be recorded when it is shipped or when it crosses a border, or possibly not.
So basically it is of no use the the buyer.
In about 10 -15 days after payment the parcel has not arrived, look on the Canada Post website. If it is in Canada, it may be there.
If it has not arrived after 20 days, go to the Resolution Centre at the bottom of this page and start a Dispute. (Allow 30 days from Asia*)
If the seller cannot prove delivery, the whole entire and only purpose of tracking numbers, he is required to refund you. If he does not, Paypal will and then go after him for for their money.
*Never accept an offer of a replacement from an Asian seller. It won't arrive either.