They have used three panels on one bar. Meaning, the curtains are not meant to move. In a more formal setting, you can easily get bars that have two rods on the same hardware and you can put your sheers on the lower bar and curtains on the one above. Anywhere you find curtain rods have the double rod hardware as well.
Enjoy your new project.

Love the accent lighting over the picture frames! adds interest to what could be a boring wall and great lighting for reading on the couch