I've had very little luck with third-party recruiters myself, personally. My take is that because the job is theoretically easier to get, there is much more competition, and the recruiters are more ruthless in removing applications that don't meet the exact specifications from their client.

Also it pains me a little for you to say that reading one book is a big sign of having lots of free time. Maybe you're not a huge reader but I hope you normally do stuff you enjoy, reading or not, whether you're employed or not, if you don't mind my saying so.