How do i find unpaired or unbounded bluetooth device in xamarin forms

Hi, i have developing a app where i need to print some text in Bluetooth printer. I have found some tutorial for show bounded device on list, but i need find a unpaired or unbounded device to show the list and connect to the device. how i get unpaired device in xamarin forms. i used a plugin https://www.nuget.org/packages/Plugin.BLE/1.1.0 for get unpaired device but when i try to connect or paired the device it doesn't response.
how can i do this. please help.
Thanks in advance