Notebook doesn't detect boot devices

Question

I want to install Xubuntu on my laptop (Asus U44SG) but it's BIOS doesn't seem to detect any device besides the hard drive.

I've tried to burn the ISO on my USB with different softwares:

1. ISO to USB
2. Universal USB installer.
3. UNetbooting.

My main PC recognizes the ISO when burnt with UNetbootin, but my laptop shows this:

(This is with the USB plugged in.)

I tried to plug in the USB with Windows loaded and restarted after it's detected, but it didn't work either.

As you can see in the picture, my BIOS doesn't let me pick the bootable USB.