search for words with different Writing or spelling in database

search for words with different Writing or spelling in database

im going to write a mail server script with php language and mysql
database.i have to put search im emails tools in my programming TODO but
there is a problem
there are some words with the same style and different encoding in some
language
for example ßÊÇÈí and ˜ÊÇÈی or ˜È˜ and ßÈß these work can be used
for each other by the user computer keyboard layout
the ßÊÇÈí and ßÈß are with arabic layout but ˜ÊÇÈی and ˜È˜ are in
persian layout
i tried to find and change one language words to other one with
str_replace function but this is not very useful because i dont know these
type of words in all language over the world
there isnt any standard for these type of words?!