Just the other day a working colleague asked me what kind of music I listen to, especially when working. It's true, music helps me to focus better and work more concentrated. But it obviously depends on what kind of music it is. And there is one project I come to every now and then. The name is Enigma. It's not disturbing, good for background, with soothing and non-intrusive vocals. Here are the songs:
Return To Innocence: This is quite likely the song you know from them, which also got me hooked up originally.
Push The Limits: A powerful song. The album version is even a few minutes longer.