The image didn't come thru, but doing a spot repair takes a fair amount of skill and is usually best done by a pro. Some of the reasons are:
- the finish is most likely not poly. I say this because poly (or any finish called 'varnish') is quite durable and wouldn't show this type of damage.
- Based on the damage you describe the finish is probably some type of lacquer. Dip a cotton swab in lacquer thinner and rub on a spot near the damage. If it gets soft, sticky or gummy, it's common NC lacquer. While NC lacquer will "dissolve' and blend into existing lacquer, lacquer's used by manufacturers (Catalyzed lacquers) don't.
- Usually damage like you describe also removes color, be it dye or stain placed on to the wood, mixed into the finish, or a toning coat. Getting a good match is difficult unless you have a lot of experience color matching.
Depending on type and degree of damage you will probably be better off stripping the entire surface and re-coloring and refinishing
Bob "Boardman" Borders