The planning info found under Map Search and through reports references data from DELWP, further information around the Zone and Overlays displayed can be found through the Planning Schemes Online website: http://planning-schemes.delwp.vic.gov.au/schemes
From here select the Municipality/LGA the property is in and from this screen you can view documents with further details about the specific Planning Zone or Overlay(s) attached to a property.
There may be both general information about a Zone/Overlay as well as a Schedule outlining more specific details.
For example the schedule below is applicable to Ballarat properties with the Zone code of SUZ1 which is Flora and Fauna Wildlife Park
Another example for an Overlay is the below which is for Bridge Mall in Ballarat and applies to the Overlay code of DDO1
Heritage Overlays differ in some ways from the other information as all of the individual codes are contained in one Schedule Document which lists each Place/Property along with specifics around the heritage controls in place