r = mui.DoMethod(id, "Search", s$, flags$)
Flags can be a combination of:
If you specify multiple of the flags above, you have to separate them using a semicolon, e.g. "FromTop; CaseSensitive".
If the string is found, it will be automatically marked. Thus, in case you want to replace it, simply clear the marked string and insert the new one.
Trueif the string was found, otherwise