Display only updated records

I have an index containing two fields "ID" and "PRODUCT_NAME". After a long time, there was a change in the nomenclature of a product, supposedly it was changed from "ABC" to "XYZ" for the same ID "P001"(i.e. we are keeping both "ABC" and "XYZ" to correspond to the same value "P001", in the index.)
Now I want to get only the name "XYZ" from the index without updating the previous data based on the ID.
Any ideas as to how to do this?
Thanks in advance.

You could use a prefix query but those aren't particularly efficient. You are better off putting a boolean value on the documents that have the new style id or putting the new style id in an entirely separate field and searching on that.

Thanks for the reply. I thought about the prefix query but discarded it due to the inefficiency.
It is a live cluster and the problem with a new field would be the display in kibana where the queries would have to be changed, but that won't be possible given a situation.
On your suggestion on putting a new Boolean value for the documents having the new PRODUCT_NAME; are you saying that we put a 0 or 1 to the data on a new field or we can do assign a Boolean value to the already present data? I am confused about this part?
Sorry if it sounds dumb, am new to it.