How does blood goes to the vain?

Blood is transported to the veins through the action of the heart, which pumps oxygenated blood from the lungs into the arteries. As blood circulates throughout the body, it delivers oxygen and nutrients to tissues and organs. Deoxygenated blood then returns to the heart through the veins, aided by muscle contractions and one-way valves that prevent backflow. Once the heart fills with deoxygenated blood, it pumps it to the lungs for reoxygenation.