How can I get the name of my laptop's internal Bluetooth adapter?
lsusb | grep Bluetooth
shows nothing, but I can use it and it's working.
Bluetooth devices are not always listed as "Bluetooth" in lsusb.
In most cases, Bluetooth adapters use the USB interface. You can run lsusb and look for it there. The word "Bluetooth" may be there or may not.
Also in many cases laptops have combined Wi-Fi/Bluetooth chips.
So most likely you will get the required information by running:
lspci -knn | grep Net -A2; lsusb
This way you will get the ID of your Wi-Fi adapter and the list of your USB devices.