Hunting close is not what setters do. They stalk/point long enough for you to get there. Retreiving breeds like the traditional lab (Springer Spaniel, ****er Spaniel, etc.) stay close and flush birds, pointers (such as English Pointers, Setters, German Shorthair, etc.) will want to range alittle (or alot depending upon terrain) but point birds til you get there (steady to wing).
Has your dog ever hesitated from scent before? Or has she always busted (chased) after birds, squirrels, etc.? If busting birds, this might take awhile as she has her way set (or it maybe she's never had the experience of a bird setting/hiding).
I never had to train an older dog before but personally, I would buy .22 blanks or a starters pistol, put her on a check chord (about 25-30' length with a simple slipknot at the end), and go to a game farm and buy a few birds and see how she does. Bring someone who knows what their doing. Much easier than trying to explain what I would do to a pup which would be very different from a mature dog.