Who clean the bad blood and give good blood

The Liver

Explanation:

The liver is the organ responsible for filtering blood in the body. It is located right below your lungs that acts like a filter for the blood. Chemicals and impurities, including from drugs and medications, are filtered by the liver. The liver have many other essential functions. For example, the liver makes and processes many body fats. Fun fact- The liver is the only internal organ that can regrow, which is why if you donate your liver to someone who needs one, the surgeons take half and eventually your half left regenerates into a whole liver again.

If you are looking for the specific vein names for which the blood travels then blood leaves the liver through the hepatic veins. This blood is a mixture of blood from the hepatic artery and from the portal vein. The hepatic veins carry blood to the inferior vena cava—the largest vein in the body—which then carries blood from the abdomen and lower parts of the body to the right side of the heart.

Hope this helps