1. Do you have a window that faces west or northwest? If yes, try it in that window. I'd go so far as to remove the screen if there is metal in it.
2. If you don't have a window that faces west or northwest, try aiming the flat surface in that direction. Try it numerous places in the room.
3. You can also try a plain old non-amplified indoor antenna. Something like
this RCA Antenna from Wal-Mart is only $10 and you can return it if it does not work. As timgr noted, the Mohu Leaf is not VHF friendly and your NBC, PBS and Fox stations are all VHF (8, 10, & 12).
4. Do you have a balcony? Try your current antenna out there. Again, as timgr noted, your HOA cannot prohibit you from putting up an outdoor antenna. They can only regulate where you put it (for example, it can't hang over your neighbor's house, etc.). An RCA ANT-751 is compact enough for using on a balcony and should work OK in your application, as would an Antennacraft HBU-11 or Antennas Direct C2V. Any of these would be worthy of consideration for the roof, as well. [Although it's possible that you may need to go a bit bigger, like an HBU-22, to get all the stations in yellow.]