I have two Asian perssimon trees over 5 years and they hardly produce any fruits. The first year (we purchased a mature tree that already produces fruits) harvested one fruit,
second year 3 fruits and no more. Every year many many fruits bloom but they do not stay on the tree and drop all on the ground throughout the season.

What do we have to do to keep the fruits until maturity? Thank you.

😫 !! 😕 Humm!!! They grow great hear in s.j. valley !!!! So...im gonna guess its either the wrong climate.
Or next year you'll get more ! And so and so forth ! Till you have to many to deal with 🙊🙉🙈😄😄😄.
Im guessin there not in pots.
How big are they ?
They are still young ! They need another yr. Or 2 ! Be patient !!!
Give em a shot of fertilizer now for good measure. It'll help um during dormancy.
They are sub-tropical ! So be sure to give em some water over winter !!!
😎😎😎