wild goose, trailing cliff radical (no. 27)
厂 centers on a wild goose, and by extension the cliff-like shape that resembles a goose in flight, which is used as a radical in other characters.
厂 is a pictograph of a cliff or a wild goose. The exact origin is uncertain, but it likely depicts a goose in flight or a cliff edge, later used as a radical.
The shape 厂 looks like a cliff edge with a goose flying off it. Picture a wild goose taking off from a trailing cliff.
For カン, imagine a can of goose food sitting on the cliff: can -> カン, and the wild goose comes to eat.