Whilst I'm dubious of their immense size, unless they constantly needed repair and never actually went on the big seagoing voyages (As the bulk of these vessels would have produce a huge amount of drag against a rather small sail area), its a nice drawing though (being unfamiliar with Junk rigging), would it be possible to show the sails hard to port?
Due to limited English proficiency, I just read your message half. . . . .However, you probably meant to say I understand.
First, the Chinese boat used is "hard sail", "hard sail" is mainly used plant leaves woven, hard and heavy, but by high winds efficiency; may rotate around the mast, to windward. Because there supporting bone, so for quality, "sail" requirement is very low, even breaking a lot of holes does not matter.
The English phrase "Hard to Port" means fully turned to port (when you are on the ship facing the front of the ship, Port is to your left), and Rodondo is asking to see the back side of the sails, if only to add to the quality of your drawing.