Wordpress - why does WP_Query parameter 's' not work?

Question

PHP

Wordpress 3.8.1. The Wp_Query "s" parameter does not work, if it is empty, then everything works fine, the answer is empty with it, although there are posts with such data.

What could be the problem? Help me please. Thank you in advance!

Code:
$the_query = new WP_Query(array(
'post_type' => 'events',
's' => $_POST['vars']['eventkeyword'],
'meta_query' => array(
array(
'key' = > 'event_companycity',
'value' => $_POST['vars']['eventcity'],
'compare' => 'LIKE'
)
),
'tax_query' =>
));

Answer 1

And if you remove everything except s? Works or not?

Answer 2

left only 's' => $_POST['vars']['eventkeyword'] - articles with type 'post' came out and 's' works (searchs) in them.