I've been fishing on a server for 5 hours with a luck of the sea 3 fishing rods according to an enchantment book with luck 1, 2 or 3. Now I wonder if you can even fish luck on an enchantment book…
I don't know if that's possible, but fishing for good things takes a long time, that's normal.
If you can, just trade with a librarian.
Yes, you can fish with luck.
Better go to a villager and put up a lectern until he sells luck. Then zombie him and heal him again. The book then only costs 1 emerald.