Question:
am i allowed to go shopping on chol hamoed in a mall i went last year and it was full of jews but someone told me this year that i cant and im wondering if thats true because last year i saw hundreds of jews shopping
Answer:
In general we should not go shopping on Chol Hamoed. However there are certain instances when we are allowed to buy things on Chol Hamoed. For example, we are allowed to buy things that are needed for Yom Tov or for Chol Hamoed itself, such as toys etc. food items. (It is preferable that it should be taken care of before Yom Tov, except for food items which may be purchased even if we deliberately waited for Chol Hamoed). The other exception is if there will be a loss if te item is not bought on Chol Hamoed, such as a sale, or the item will be sold out.
Sources:
O:CH 539-1, 536-1, Piskei Halchos Of R” M. Feoinstein Zt”l in the back of Hilchos Chol Hamoed.