How much time does it take to die from multiple stab wound to the chest & abdomen?

Depends on severity: You can bleed slow or fast from stab wounds. Much depends on which vessels are injured. Surprisingly, big veins bleed worse than arteries-it is harder to see where the bleeding is coming from. Some people bleed a great deal, then the BP gets low and the bleeding stops. They can potentially survive for many hours, if they are young.