Query for Left(String,5) - Access 2007

I found this response in a post regarding a query I'm trying to do. It looks
like it's what I need but I don't know how/were to implement it in the query.

what I found
do you have these zip codes stored already? Then just use this in your

Left ([YourField], 3)

If not than create a zip code table and include the zipcode field in the
query. Then set the criteria similar.
Good luck

I have a table(excel file) of 5 digit zipcodes.
I'm linking it to a name-address table that has a 9 digit zip.
I only find records with the exact 5 digit match - not the many that have +4

How/where do I add the left(yourfiled,5) above.
I've always done this by adding a like function in the zip filed for all the
zips I need but the above method would be much clearner and easier - assuming
I can learn how to do it.