Sorry to reply in English, but my French skills (3 years at grammar school, about 15 years ago) are too limited to clarify that my mod won't work as demanded, simply as I've misread the requirement.
My mod will change every search character with an accent to its equivalent without an accent (search for "transliteration" for more information). So regardless if you search for évite, évité or evite, it will always just will find "evite". This may work if you just use keywords without accents, but I assume this isn't the case. Of course you could also replace each accent character with a placeholder, which matches every character, but this is probably not what you're looking for. I don't know if there are transliteration functions in MySQL (I doubt so). The easiest solution is maybe to use my mod AND replace all characters with accents in title/description/keywords with their equivalents without accents in your gallery.