rst/themes/lifescience-theme/searchbox.html (5 lines of code) (raw):
<form action="{{ pathto('search') }}" method="get">
<input type="search" name="q" class="uui-search" placeholder="Search"/>
<input type="hidden" name="check_keywords" value="yes" />
<input type="hidden" name="area" value="default" />
</form>