[TYPO3-english] Indexed_search problem with utf8

[Girmangus Hailu]

I have a multi language site and I have installed the indexed search
plugin. the indexed search search and brings me a result of number,
date and english words but when I try to search using utf8 characters
it doesn't show me the result, it simply says "no result found". I
have checked the index fulltext and it has already the keywords that
i'm searching for. I try to fix the preg_replace with /u and it
doesn't show me any thing. pls help me guys.I know this problem face
everybody before. I'm waiting for ur response and feel free to ask me
if u need additional information.

I thank you,
Girmangus H