If you often soak your feet in water boiled with mugwort leaves, it will put your above mentioned problems such as feeling cold in the spleen and stomach, cold body, cold hands and feet. Certain body parts with stasis, or low immunity will have a good improvement.
My second brother and sister-in-law. Have been soaking their feet in water boiled with mugwort leaves for a long time, probably a couple of years as well. So they soak their feet everywhere they go, and sometimes they use hot water to soak their feet even if they don't have mugwort boiling water.
My second brother and I said that since soaking his feet, he feels that his legs and feet are warm, and he feels that his legs and feet are more numb, unlike some old people who have no strength to walk, and their legs and feet are painful, and after soaking his feet, his legs and feet are lighter than the young people's walking and look brisk. Because my brother is 70 years old. So moxa leaves boiled water foot soak is very good, if you do not have moxa leaves, but also often hot water foot soak. It is very crucial to unclog the meridians and activate the qi and blood.