Only search one column, then highlight all cells in that column with more than (a number) characters, so i change the data one by one?
Its phone number, thousands of them, many are typed incorrectly, at least 100, i try to find them directly without going through all of them
If you want to highlight cells which contain more than X characters, you can use
Conditional formattingand function
For example: You want to highlight all cells in column A containing more than X characters.
=LEN(A1)>X(X is any integer larger than 0)
See Excel help for better understanding.
PS: I don't have English version of the Excel, so some names can be little different.