Seems like your air ventilation inside your engine compartment not good enuogh.
That's why when you open the bonnet your air become cooler coz fresh air come in.
Better you check your condensor fan functioning or not. If yes, then check the speed
of the fan.Afraid not rotate fast enough to cool the condensor.
Thanks for your advice.
actually, there are two problem
(1) the water/coolant need to be change.
Last month i drain out all water/coolant. The water is in red/orange color showing a lot of rust accumulated in the water/coolant. After put in new water/coolant the engine temperature is lower now.
(2) Yesterday i went to an aircond service shop. They said the compressor is very weak.
So i let them change the compressor. They have 2nd hand Kancil compressor which they import directly from Japan.
They said in Japan, people drive Mira for 3 or 4 years than change new car. the old car than taken apart and spare part are being export to Asian countries as 2nd hand spare part.
So now i have a 2nd hand compressor which is made in Japan.
Really happy with this 2nd hand compressor. My Kancil is now very cool even under hot sun even when car not running with only engine running at idle speed!