search-string
    Specifies a quoted string indicating the string to search for.

    If the TPU pattern style is being used the search-string is a
    TPU expression which must evaluate to a TPU pattern (for
    example: "'abc' | 'def'").

    If you are using the DECwindows interface and specify the /DIALOG
    qualifier, the search string field in the Find dialog box takes
    the default value from the the previous search string, if any.