You need to find out if it has been treated with Amtico polish. If it has, then it needs to be sripped with Amtico polish remover.
More often than not, it won't have been treated. A rotary scrubber, as above, will clean out the scratches and the gaps where the dirt has settled in them.
When dry....2 or 3 coats of Amtico floor polish will make it look the mutts nutts and will also hide the scratches.
Have a look at the Amtico web site for more info. All the relevant info used to be on there.