Thanks for All your answer.

Finally I found out that How discovery works on this location and in yours answer, too


'''
(https://github.com/dan-da/hd-wallet-addrs)
In plain english, discovery works by mathematically deriving the addresses for your wallet in order and checking if each one has been used or not.

A slightly more technical description of the process:

starting from the extended public key (xpub)
for receive addresses, then change addresses
derive batches of xpub child addresses (bip32: 0/*)
for each batch
check if each address has received funds (API call to oracle/server)
until 20 (default) unused addresses in a row are found.
'''


thanks so much

Then, when the electrum wallet loads a new xpub, or when the blockchain explorer retrieves the entire transaction or address by referring to the master public key,
Is it reading way from m / 0 and stopping if there is no balance or transaction?
For example, the 30th time, if there is no balance or transaction in the retrieved child key, it stops.

Hello
I have a question while implementing along blockchain bip32.
I understand that bip32 can generate infinite addresses such as m / 0, m / 1, m / 9999 ..
I am wondering if there is a fixed rule to search the line when searching the blockchain full node for keys expanded by bip32 such as xpub in blockchain explorer.

It's not going to search all the infinite addresses, but if you know, please help.