Category Description not found

Yes and no: Relevanssi indexes category description, but only for the categories themselves, which requires Relevanssi Premium. The category description is not indexed for the posts in the category.

With the free version, you need some filtering in order to make this work. You can use the relevanssi_content_to_index filter hook to add any content you want to to the posts before they are indexed, so you can write a function that will fetch all categories for the post and adds their descriptions to the post content.

If you’re using OR search, you can also add those synonyms in Relevanssi synonyms settings, that works as well.

Yes, you’d have to, because with Premium, you still wouldn’t get all the posts: if you indexed the taxonomy terms, then searching for “Almighty” would return the category “God”, not the posts in the category. In order to find posts by the category description, you need the filter function.

Here’s the filter function you need:

add_filter( 'relevanssi_content_to_index', 'rlv_category_desc', 10, 2 );
function rlv_category_desc( $content, $post ) {
	$categories = get_the_terms( $post->ID, 'category' );
	$descs      = array_map( function ( $cat ) { return $cat->description; }, $categories );
	$content   .= implode( ' ', $descs );

	return $content;
}

Add this to your theme functions.php and rebuild the index.

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