Wa Alaikum Salam.
If engine health is perfect, and you do not face any oil consumption issues or smoke from the exhaust, etc., then from next oil change, try ZIC 10w-40 fully synthetic (else if switch back to 20w-50, if something gets messed up).
Similarly, if you do not face any major oil consumption issues or smoke from the exhaust, etc., on 10w-40, then from next oil change, try Caltex / Havoline 10w-30, else if switch back to 10w-40 or 20w-50.
Lastly, if you do not face any major oil consumption issues or smoke from the exhaust, etc., on 10w-30, then from next oil change, try 5w-30 fully synthetic from any of Shell, Total, KIXX, Caltex / Havoline, or may be even PSO, else if switch back to 10w-30 or 10w-40 or 20w-50.
Just ensure that oil is 100% authentic in all cases, and change oil + oil filter after every 5,000 Kms / 06 months, whichever comes 1st. If oil level drops in-between, simply top-it-up.
Use genuine oil filter always, which lasts at least 5,000 Kms, and stick to the oil grade + brand, which suits the best.