Good day mga bossing!

I tested my car, at 10+km drive the whistling and squealing sound began again, but the temp gauge was at half and it sucked the overflow water but not that much. When I stopped the car and open my engine bay and immediately inspected it for any leaks from the cooling system, but nothing seem wrong...

what other possible things that causes those sounds from my engine? please I need help badly, I have to travel next week and I really need my car...

thanks again