Keyword

<?php
$keyword= 'keyword1 keyword2';

$search_word=explode(' ',$keyword);

foreach ($search_word as $word){

    //echo  $word."<br />";

    $where_list[]="`question` LIKE '%$word%'";//SQL

    $where_clause = implode(' OR ',$where_list);

}

if(!empty($where_clause)){

    $search_query .= " WHERE $where_clause";

}

echo $search_query; //WHERE `question` LIKE '%keyword1%' OR `question` LIKE '%keyword2%'
?>