You could use a loop, but a relationship and Go TO Related records can do it all in one step too.
If you list all your part numbers in a single text field--likely a global text field, you can use it as a match field to your part number field in your table of part numbers and then Go TO Related Records can pull up the matching set of part records.
LayoutTableOccurrence::PartNumberList = Parts::PartNumber
Go To Related Records [Show Only related records ;From Table::Parts ; Using Layout "Parts" (Parts) ]
Your layout and table occurrence names may differ from mine and so you'll have to use yours in place of mine.
For scripted finds--including that loop, see:
You're doing the Find so you can.... Do ____ / List _____ / ??
Usually Find is a means to an end. If we know better what the goal is, we might have better suggestions--or an alternate route. :-)
If you have some sort of delimited list, the process philmodjunk described is the easiest/fastest way to get a found set of the records you need.
You may want to think about a way to identify bad numbers. It happens sometimes and you might need to know some of the numbers were not found at all and which ones they were.