Print-debugging in Telescope action (or when `silent` enabled?)

I’m learning how Telescope’s actions.set.edit works by putting some print() in the function (for example here).
But any print() there doesn’t take effect with no error. :messages command shows nothing.

In addition, I’m surprised that even writing on a file by the code below doesn’t help:

-- None of these do nothing. No error.
vim.fn.writefile({"message"}, "debug.log", "a")
vim.cmd("echomsg \"" .. "message" .. "\"")

local f ="debug.log", "a")

How can I avoid the problem?

My environment: NVIM v0.9.0 on Windows 10.

I’m really not sure why, but the problem isn’t reproduced today…

Update: I learned the debug code wasn’t actually executed. Sorry for making a confusing thread.