Bibek ji,

So basically there is no way to determine that as for every visitor visa you need to prove you will return back to the country of origin or the residence. Along with that you will have to prove you have sufficient funds for your travel.So the officer mainly looks at this and decides whether they want to give you the visa or not.
Another criteria they may look at is your health.

To increase your chances:
if you have family or relatives in Canada and can write you a letter of sponsorship covering your food, accommodation it increases your chances.
You can show the entry and exit stamp on your passport as this shows the proof that you returned back from your trip.

I hope this helps :D