That's pretty much the respose I get to when I talk about hunting quail with an air rifle.
The only advice I could give is to find a spot that you know where they are (either you have seen them, without them seeing you, or you can hear them). Then find some decent cover where you think they are nearby and where there are a few clearings. Then it's a waiting game. When they come out, then you can take aim and score one. In my limited experience, most I've seen are out foraging very early in the morning when the sun is just allowing enough light for them to see the eats on the ground or bushes. If they spot any movement, they are off in a heartbeat. So being well camo'd is important and having good cover helps to conceal you even more. Hunting quail with an air rifle is a real tough one. When I tell quail hunters that I am going to try for quail with an air rifle, they basically give me a look like I just told them I'm an alien from Pluto. Then they tell me that I'm in for a real difficult hunt. Which is true. However, if you know the animals behavior and habits you can increase your chance of success that much more. I hope you get some and I hope I get some too.