单表筛选

=IF(ISERROR(INDEX(Sheet1!A$1:A$21,SMALL(IF(Sheet1!$B$1:$B$21=--MID($M$1,1,1),ROW($A$1:$A$21),28),ROW(A1)))),"",INDEX(Sheet1!A$1:A$21,SMALL(IF(Sheet1!$B$1:$B$21=--MID($M$1,1,1),ROW($A$1:$A$21),28),ROW(A1))))