separate, divide, topped rice radical (no. 165)
釆 centers on separating or dividing something, often in the context of grain or rice. The radical sense is a topped rice shape used as a component in other characters.
釆 is a pictograph of a rice plant with grains separated at the top, representing the idea of dividing or separating grain. The modern form retains the rice-like shape with an extra stroke indicating separation.
Picture a rice plant with grains at the top being separated from the stalk. The extra stroke above 米 shows the grains being divided off.
For ハン, imagine a hand separating rice grains: hand -> ハン, and your hand divides the topped rice.