What causes rumbling noises in stomach when trying to sleep or at night. not hungry but when stomach makes los noises all night ?

Possible: possible poor digestion could cause increased gas which could cause some of that. consider use of digestive enzymes and limiting liquids with meals food allergies also a thought.

Some basics: You swallow air every time you eat which must leave your gut as a burp or fart. Your stomach is a muscular organ that churns the food/air mix preparing it for digestion. Material passing through the gut is either absorbed or left behind where bacteria can digest the left over nutrients, often creating gas. The air/gas movement you notice may be either stomach or intestine.