Carol,
Let's nail this in three steps.
Make a new formula field called Search Target with the formula
List(" ", [First Name], [Last Name], [Tax ID], [PIN])
Put that field on the report and observe that the search for John Smith works.
Then, you can make a new formula rich text field called Hidden Search Target.
"<a name=" & URLEncode([Search Target]) & "</a>"
add that to a report. Either name the rename the field like a dot . or else do a column override on the report to have a . or blank for the column name and put the field at the far right of the report where users will not really notice it.
That allows you to make a hidden column with all the possible search terms you want without cluttering up the report with extra visible fields.