So the code is made up entirely from the description? Yuck, it would be much better to replace the description with a lookup into another table. Or is this what you're trying to do?
If it were me, I'd have the correct descriptions in one table and generate the list of descriptions that weren't in the table & do replacements for eg. BK -> BOOK until the list of exceptions was empty.
If you don't have a list of codes/descriptions in a table then it makes it harder, soundex style searches can be useful but it depends on whether you have lots of words that sound alike.
How many codes are you talking about anyway?