WooCommerce does not support this specific scenario. The primary issue in this case being that WooCommerce processes orders at the order level NOT the line item level.
So if a customer were to order items from multiple sellers you create a situation that will cause serious problems and headaches. When the first seller marks the order as processed the entire order (each and every line item) is also marked as processed. Even if the seller of the second or subsequent line item(s) haven’t processed the order.
Those items would never be made, packed, or shipped.
That being said you can filter the WooCommerce admin order view by using woocommerce_custom_order_views(). You can see the documentation at http://wcdocs.woothemes.com/apidocs/function-woocommerce_custom_order_views.html
Since products are ‘posts’ each product has a post_author that would equate to the author/creator of the product. Each order has a serialized list (wp_postmeta._order_items) of the line items, including the line item’s wp_posts.ID
So with a bit of work you could determine which orders contain items created by a specific seller (user), then filter the display appropriately.