How many customers have cancelled orders? | Do you mean the customers in the previous result? | yes
SELECT count ( T1.customer_name )  FROM customers AS T1 JOIN orders AS T2 JOIN order_items AS T3 JOIN products AS T4 ON T1.customer_id  =  T2.customer_id AND T2.order_id  =  T3.order_id AND T3.product_id  =  T4.product_id WHERE T3.order_item_status  =  "Cancel" AND T4.product_name  =  "food"
count of customers = COUNT(customer_name); customers who have cancelled orders refers to WHERE order_item_status = 'Cancel'; the context of 'customers in the previous result' implies filtering on a specific condition mentioned earlier, in this SQL it's implied to be related to 'food' products.