Dear @HANG, welcome to the Community.
Have you already had a look (i.e. a search) to the previous posts in the forum ?
There are many hints regarding Nano33_BLE-AI2 communication.
Just one example is : App inventor - Arduino Nano33Ble communication issue - #9 by darnell.
Maybe you can find the solution, there.
Another (huge 
) source of information is @Juan_Antonio's web site KIO4.com
Best wishes.
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