Use the program that created the backup file to extract only the files that
you want. If the backup file is on a USB hard drive, install the program that
created it on the other computer and attach the USB drive to the other
computer.
If the program can't extract individual files, restore the backup to the
original computer, copy the files that you need to the USB drive and then
attach the drive to the other computer. Copy them off the USB drive to the
other computer.