OPEN
includes/search/fulltext_mysql.php


FIND
		<dl>
			<dt><label>' . $user->lang['FULLTEXT_MYSQL_MBSTRING'] . '</label><br /><span>' . $user->lang['FULLTEXT_MYSQL_MBSTRING_EXPLAIN'] . '</span></dt>
			<dd>' . (($this->mbstring_regex) ? $user->lang['YES'] : $user->lang['NO']). '</dd>
		</dl>

AFTER, ADD
		<dl>
			<dt><label>' . $user->lang['MIN_SEARCH_CHARS'] . '</label><br /><span>' . $user->lang['FULLTEXT_MYSQL_SEARCH_CHARS_EXPLAIN'] . '</span></dt>
			<dd>' . $config['fulltext_mysql_min_word_len'] . '</dd>
		</dl>

OPEN
language/en/acp/search.php

FIND
	'FULLTEXT_MYSQL_PCRE_EXPLAIN'			=> 'This search backend requires PCRE unicode character properties, only available in PHP 4.4, 5.1 and above, if you want to search for non-latin characters.',

AFTER, ADD
	'FULLTEXT_MYSQL_SEARCH_CHARS_EXPLAIN'	=> 'Words with at least this many characters will be indexed for searching.  You or your host can only change this setting by editing your mysql configuration file (my.cnf).',