Ok, so i have to add some more focus on the search form on a Simple Machine Forum search form. The users seems not to take into account this option, so as a result a lot of duplicate topics appear daily.
This is how the search form looks right now (it's the default theme with some colors changed).

I want it to be wider as the forum is and with some style applied on it.
First, i will remove the lines (from 298 to 302) regarding the news field, which i will not use from the Themes/default/index.template.php :
if (!empty($settings['enable_news'])) echo ' <td width="90%" class="titlebg2"> <span class="smalltext"><b>', $txt[102], '</b>: ', $context['random_news_line'], '</span> </td>';
than add to the first td line which include the search form a colspan="2" attribute so it will become