If the search is on two properties, choose a union operator.
If two property value ranges are set then two searches are performed, one on each range of values. The result of the double search is displayed in a single list and the Property Search utility must know how to combine the two searches. The Union operator determines the method of combining the searches.
AND An element must have matched the criteria of both searches in order to be included in the final results.
OR An element will be included in the final result if it is matched in either search.
The union operator is displayed only if two properties are set for the search The default selection for the union operator is the logical AND