Here's what I would try:
* remove every CFL/fluoro lightbulb in the house (especially the cool white ones) and replace them with warm-white globes, preferably LED.
* warm shower/bath about 45 min before bed - when the body starts cooling down sleep is more likely
* no milo/chocolate drinks in the afternoon or evening (too stimulating). Same goes for chocolate flavoured desserts
* If she has a light in her room (eg, nightlight) get one with a red bulb - as that's the colour that least stimulating
* Spend some time in the bedroom with her. In our house that meant moving the bedtime story reading into her room, instead of on the lounge.
* Sometimes the restlessness is actually a sign the child is overtired. Maybe send her to bed a bit earlier and see what happens?

If you've tried all that and are still getting no progress, you might need to see a dr.