In order to improve the probability of catching fish, you can use fishing rods with fishing skills, such as
Coarse iron fishing rod
Emancipated hands
fishing rod
(This fishing rod can be bought at the auction house) Equipment: fishing skills are improved by 20 points.
Champion of Thorn Valley Fishing Competition: Jin Ao Fishing Rod
Post-delivery binding
Equipment: fishing skills increased by 40 points.
Dalaran daily fishing bag: jewelry fishing rod.
Binding after picking, equipment: fishing skills increased by 30 points.
There is also an openable "storm fishing hat" in the daily reward package for fishing in the four major cities.
Nat pagle Le, a fisherman quartermaster in Kasanlang jungle on pandaren Island, sells sharpened walrus harpoons.
Daily recipes for fishing: Captain Ramsey's special beer.
Captain Ramsey's special beer can also improve your fishing skills.