A pro tip to remember the difference between Bunlar and Sunlar. Bunlar (these) in English alphabets B comes in the beginning so Bunlar is for something near because the things near to you are the first things you see so they are referred to as Bunlar(These) and similarly B is one of the first Alphabet. On the other hand alphabet S comes very late thus meaning very far and the things that are far referred are to as Sunlar (Those).
You can also say alphabet B comes first thus meaning near so Bu/Bunlar (This/These). On the other hand alphabet S comes very late thus meaning far so Su/Sunlar (That/Those). And O is like calling someone who is very far away from like for example "Oi listen to me bro" so O (That / Those) but for something far away.