do you walk around barefoot? could be an idea to wear socks or slippers around the house, also if you are just sitting about rather than moving the blood flow will be reduced and you will notice this more. get up and move more frequently.
Also sitting cross legged stops the circulation as much and will also make your feet feel colder. It is normally your hands arms and feet that are exposed in the house. What kind of flooring do you have, wooden, laminate, lino etc these can also make a difference.
some things like cayenne pepper as coltdan said above help as well as horse chestnut, hawthorn, ginger and garlic are all well known for this.