How does a blood clot travel from the right leg to the lung?

Blood comes into your heart through the veins all throughout the body, it enters the heart through the superior and inferior vena cava, leaves the heart though the pulmonary artery, enters the lungs, gets oxygen, enters the heart again through the pulmonary veins, and then leaves the heart and goes back throughout the body through the aorta.

So blood travels from the heart, to the lungs, back to the heart, than out the heart and all through the body.