What should I check first if debugging trick doesn't apply?

Hello!
I was excited at all the features your plugin offers and read many highly positive reviews, so I recently installed. Thus far, it seems almost no search for any of my content yields results.
I think my search.php is OK

<?php get_header(); ?>

	<section id="main">
		<section class="top"></section>
		<section class="bottom"></section>

		<br />

		<section id="page">
			<header>
				<?php share_buttons(); ?>
				<?php js_breadcrumbs($post->ID); ?>
				<h1 class="bitter"><?php _e('Search Results','glory'); ?></h1>
			</header>

			<article id="content" class="left">

				<?php if ( have_posts() ) : ?>

					<ul class="archive-list">

					<?php while (have_posts()) : the_post(); ?>

						<li>

							<?php if (has_post_thumbnail($post->ID)){ the_post_thumbnail('thumbnail'); } ?>

							<div class="post-content<?php if (!has_post_thumbnail($post->ID)){ ?> no-thumb<?php } ?>">
								<h4 id="post-<?php the_ID(); ?>"><a href="<?php the_permalink() ?>"><?php the_title(); ?></a></h4>

								<?php if (of_get_option('js_hide_metainfo') == 0){ ?>
									<p class="post-meta"><?php _e('Posted on','born'); ?> <strong><?php the_time('F j, Y') ?></strong> <?php _e('by','born'); ?> <?php the_author_posts_link(); ?> <?php _e('in','born'); ?>
									<?php the_category(', '); ?><br /><?php comments_number( __('No Comments','born'), '<a href="'.get_permalink().'#comments">'.__('1 Comment','born').'</a>', '<a href="'.get_permalink().'#comments">% '.__('Comments','born').'</a>' ); ?></a></p>
								<?php } else { ?>
									<br />
								<?php } ?>

								<?php the_excerpt(); ?>

								<a href="<?php the_permalink() ?>" class="more"><?php _e('Read More','born'); ?></a>
							</div>

							<div class="cl"></div>

						</li>

					<?php endwhile; ?>

					</ul>

				<?php else : ?>

					<h2><?php _e('Nothing found','glory'); ?></h2>

				<?php endif; ?>

				<?php js_get_pagination(); wp_reset_query(); ?>

			</article>

			<section id="sidebar" class="right">
				<?php get_sidebar(); ?>
			</section>

			<div class="cl"></div>

		</section>
	</section>

<?php get_footer(); ?>

What should I check next?

Thanks in advance!

https://wordpress.org/plugins/relevanssi/