Worth mentioning: the amount of spells you receive via the Draw command in battle is influenced your Magic stat. If it’s low, you’ll only get 2 or 3. At 100, you’ll always draw 9 per turn
Also, not every spell is useful. Don’t feel obligated to max out on every spell that comes along. Some are ONLY useful for junctioning. Some are only good for casting. Some aren’t any good for either!
Always check every new enemy for new stuff to draw. If a draw target is being particularly stubborn and keeps failing, it might be a new GF, so keep trying.