Can anyone please explain Article 1503 and Article 1504 of the Law on Sales (Philippines)? This is for understanding purposes, so a thorough yet simple explanation would be appreciated. Thank you!

Art. 1503. When there is a contract of sale of specific goods, the seller may, by the terms of the contract, reserve the right of possession or ownership in the goods until certain conditions have been fulfilled. The right of possession or ownership may be thus reserved notwithstanding the delivery of the goods to the buyer or to a canier or other bailee for the purpose of transmission to the buyer. Where goods are shipped, and by the bill of lading the goods are deliverable to the seller or his agent, or to the order of the seller or of his agent, the seller thereby reserves the ownership in the goods. But, if except for the form of the bill of lading, the ownership would have passed to the buyer on shipment of the goods, the seller's property in the goods shall be deemed to be only for the purpose of securing performance by the buyer of his obligations under the contract. Where goods are shipped, and by the bill of lading the goods are deliverable to order of the buyer or of his agent, but possession of the bill of lading is retained by the seller or his agent, the seller there by reserves a right to the possession of the goods as against the buyer. Where the seller of goods draws on the buyer for the price and transmits the bill of exchange and bill of lading together to the buyer to secure acceptance or payment of the bill of exchange, the buyer is bound to return the bill of lading if he does not honor the bill of exchange, and if he wrongfully retains the bill of loding he acquires no added right thereby. If, however, the bill of lading provides that the goods are deliverable to the buyer or to the order of the buyer, or is indorsed in blank, or to the buyer by the consignee named therein, one who purchases in good faith, for value, the bill of lading, or goods from the buyer will obtain the ownership in the goods, although the bill of exchange has not been honored, provided that such purchaser has received delivery of the bill of lading indorsed by the consignee nomed therein, or of the goods, without notice of the facts making the transfer wrongful. (n)Art. 1504. Unless otherwise agreed, the goods remain at the seller's risk until the ownership therein is transferred to the buyer, but when the ownership therein is transferred to the buyer the goods are at the buyer's risk whether actual delivery has been made or not, except that: (1) Where delivery of the goods has been made to the buyer or to a bailee for the buyer, in pursuance of the contract and the ownership in the goods has been retained by the seller merely to secure performance by the buyer of his obligations under the contract, the goods are at the buyer's risk from the time of such delivery; (2) Where actual delivery has been delayed through the fault of either the buyer or seller the goods are at the risk of the party in fault. (n)