Cross Reference between documents

I think this is a cross reference question, not sure though.

I have an excel document of about 5,000 clients/rows (containing names, addresses, lease numbers, and product numbers among 9 other things). In a new blank document I have about 300 random clients and I only need 4 columns (name, product number, model number, and lease expiration date). My biggest problem is there is no sort order I can put them in and I have to go manually hunting for each client in the list of 5,000 to find the one I need.

I really don't want to have to CTRL+F each person from the list of 5,000 and manually copy and paste each column I need.

Do I need a macro? IS there an easier way? Any help would be much appreciated!

Thanks again