Short, sweet, and cheap.
How do you think your application pool would change if your classified looked like this?
Sure, it costs a whole lot more. But you get what you pay for. The first ad will get everyone looking for a job (which is quite a bunch of people). The second ad will only get those people who read that description and see themselves in that role. The ad becomes an automatic filter for you, weeding out many of the undesirables.
Plus, that second ad might get the interest of someone who never knew she was perfectly suited to work for you. She would have ignored the first ad.
When it comes to classifieds, you get what you pay for. More importantly, you get what you ask for. So ask for exactly what you want. It is worth paying a little more.
PS The second ad also gets attention for your business. Someone might read that ad and even though the job is not for them, the description of the position gets them thinking, "Yeah, I'd like to shop somewhere that hires people like that."