Sayyed Mohammad Al-Musawi, Sayyed Mohammad al-Musawi is originally from Iraq and heads up the World Ahlul Bayt Islamic League in London. Other than being involved in various humanitarian projects, he frequently responds to... Answer updated 3 years ago

Usually, supermarkets in non Muslim countries sell variety of items which are either allowed or Haraam. The money earned from selling the Haraam items is not permissible while money earned from selling Halal items is allowed. Try to know the ratio of it as much as you can.

You need to avoid using the Haram part of the money as much as you can.