My phone is a Sony Ericsson j10i2 , the windows system is Windows 8. I can send files from PC to phone but not vice versa, because my phone doesn't find my PC, and Bluetooth settings are correct "allow Bluetooth devices to find this computer"
If you can send files from PC to phone, it means the both devices have already been paired up. So, you don't need to find your PC at all whether its discoverable or not. Just look in the list of paired devices on your phone (I am not familiar with interface of phone, so I can't help with this). Also remember, Object Push Profile (OPP) is required on phone to send files (verify this in "About Bluetooth" section).
Another way to fetch files from the phone: In bluetooth software of PC, you can see "Browse files from the device". Use it & right-click on files/ folders you want to fetch (OBEX FTP Bluetooth profile is needed on the phone for that).