Question

Why cloud don't forms ice in minus 35 degree in the sky.

Answer 1

because of low pressure, water will be in vapour state

this is the only possible explanation to your statement

P.S I don't think your statement is completely true

okay, I googled and got this answer

In fact, the same cloud can be partly composed of water drops and partly composed of ice crystals. Clouds have no problem existing in the cold of winter, because they can just exist as ice crystals. In fact, even in the summer some of the clouds you see are composed of ice crystals

so yes, your statement is not completely correct

Answer 2

Helo mate here your ans

Because The water drops or ice crystals in the air are usually too small for you to see them individually, so instead you see a white or gray haze. For instance, with every breath you exhale, you are blowing out water vapor that has evaporated from your lungs. You don't usually see your breath because the vapor you exhale stays in the gas state. But when the air outside is cold enough, the water vapor you breath out quickly condenses to little drops of liquid water and you see your breath as a small could.

Hope this ans help you