Every buyer can add to his shopping cart as many products as he wants. The products don't have to be from the same seller. After the buyer continues with the buying process, the order will automatically divide to the different sellers. Every seller will receive his own order and the buyer will be able to view each one of the orders in his account.
The purpose of this option is to make the buying experience more convenient for the buyer.
Note: Pay attention that the order may require different shipments from different sellers or even from the same seller (for example: lead time of products is different).