r = mui.DoMethod(id, "Search", s$, flags$)
Flags can be a combination of:
FromTop
CaseSensitive
Backwards
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.
True
if the string was found, otherwise False