How to lookup the bluetooth address in surrounding?

I want lookup one or more bluetooth device(s),which in be find mode,with a bluetooth module.But up to now, I haven't find any data on this .I guess there is something like *.lib gives out the functions to do this. Any suggestion would be very appreciated.

You might have to provide at least a link to your module (there are a bunch of them out there and every manufacturer knows best how the user loves to talk to their module). I don't know how *.lib should be related to Arduino, I never seen any file for the platform named like this.

As pylon says there are several different BT modules but they basically boil down to 2x types. Slave only modules that can only receive connections and Master/Slave switchable that can initiate or receive connections. You may also have different BT protocols to think about as BT devices can be one or more types like HID, Serial & Audio.