Sometimes two or more property values are required in order to retrieve values from the data source. For example, during manual indexing you must enter the vendor name and invoice number in order to retrieve information from the data source.
If the vendor name will always be entered first and the invoice number second, make the invoice number the trigger property.
One of the profiles will be initiated when the vendor name is entered and the other will get initiated when the invoice number is entered. Because each of the profiles require both the vendor number and the invoice number in order to return values, only the second profile initiated will retrieve additional values from the data source.