Yes, there is a way to target the zip code of an area. When running the report, you are going to get the criteria ID for the zip code, which will be different than the actual zip code. If you look at the
Geographical Targeting criteria codes, you can find the criteria IDs corresponding to its zip code.
You can return the name and other useful information of the
MostSpecificCriterionId by using the
LocationCriterionService. However, there is no guarantee that the MostSpecificCriterionId will be the zip code because it is determined by the most specific criteria code that is associated with your Impressions.