high vibration when apply break speed between 100 to 80 km ph

The vibration is probably the brake rotors .Look for small spots on the rotors .you want to see a smooth shinny surface and any discoloration or rust will cause vibrations. That will cause the pads to wear faster . If the car sits for days at a time the pads tend to rust or if the pads are heated a lot when cooling they can cause distorion and warping this also can cause a vibration The hardness could be coming off the rotors and if it is it will only get worse . So you may need to get the rotors changed soon