bag, purse, sack, put in bag
囊 centers on a container made of flexible material: a bag, purse, or sack, and by extension the act of putting something into such a container.
囊 is a phono-semantic compound. The outer shape is related to 衣 (clothing), suggesting a cloth container, while the inner part likely contributed the sound. The modern form is complex and its exact historical development is uncertain.
The top looks like a tied opening, the middle is a full belly, and the bottom 冖 acts like a sealed base. Picture a bulging cloth sack cinched at the top.
For ノウ, imagine a sack so full that you say 'No!' when asked to carry it: 'No!' -> ノウ, and the bag is stuffed.