Woodworkers ?

Depending on the depth of the scratch and the thickness of the veneer. First rule of thumb, less is more in such matters. I would try a very fine grit sand paper (no less than 220, depending on the depth of the scratch) and use a soft rubber backed block or the palm of your hand, DO NOT use your fingers and focus on just the scratch other wise when you refinish it will be noticable. Let the paper do the work and be gentle and always sand with the grain, always gently. To get the sheen back use progressively finer grits of paper and 0000 steel wool. Talk to the manufacturer about the finish and stain (if any) used. I would imagine lacquer is what most use, faster and less labor intensive, although some may use an oil finish.

If in doubt about the above, leave it alone or let a professional look at it.

J K I do see your concern but my concern with a very fine grit paper like 600 or higher is that it may bring out more sheen than the original finish and thus show up more. These grits are primarily for sheen, polishing and removing irregularities between finish coats. I do however agree that 220 may indeed be too course. If the scratch is deep it should be fine so long as due care is given. If the scratch is very slight I would go with a 320 or maybe 400 and GO LIGHTLY. This way there is less risk of matching up the sheen with the original finish. Refinishing is a learned process. Touching up a scratch without any noticable effects is a very skilled learned process. It is best to experiment on an area of the cabinet that isn't noticable, if any, especially if there is any doubt.

Amen to a plane over sandpaper

Prfont I would certainly take more stock in what a professional restorer offers. I am a hobbyist although I have extensive and many years experience in such matters but in reality my advice isn't for novices. Listen to the expert.