Unfortunately, I have tried these two methods, but still can't solve it. I have tried re-downloading the game, restarting the power, deleting other irrelevant applications, turning off the firewall, changing the language, making sure the file is complete, etc, but still can't solve it. I guess this problem may be caused by my old equipment, and other games developed by renpy also have some similar problems, but they are not too serious like that.
ps: thank you very much for your reply about the book. d(OuO d)