Make sure that the mobile has Bluetooth activated. Also, you might also need to make sure that the mobile's bluetooth is set to broadcast.
In the case of most mobile default settings (Sony Ericsson w350a is mine), it is set to receive bluetooth requests only. Most bluetooth earpieces are set to broadcast which is why your phone will see them.
Look up the instructions on Bluetooth and set your mobile to broadcast and your laptop should see it.
Hope this helps