SELECT events.id, events.name as event_name, events.date_start, events.date_end, events.country_id, events.description, events.day_1, events.day_2, events.month_1, events.month_2, events.year_1, events.year_2, events.is_present, links.links, images.images, countries.countries, clusters.clusters FROM events
LEFT JOIN (SELECT countries.id, event_to_country.event_id, GROUP_CONCAT(countries.name) as countries FROM countries LEFT JOIN event_to_country ON countries.id = event_to_country.country_id GROUP BY event_to_country.event_id) as countries ON events.id = countries.event_id
LEFT JOIN event_to_country ON event_to_country.country_id = countries.id
LEFT JOIN (SELECT event_id, GROUP_CONCAT(link) as links FROM links GROUP BY event_id) AS links ON events.id = links.event_id
LEFT JOIN (SELECT event_id, GROUP_CONCAT(name) as images FROM images GROUP BY event_id) AS images ON events.id = images.event_id
LEFT JOIN keywords ON events.id = keywords.event_id
LEFT JOIN (SELECT country_id as c_id, GROUP_CONCAT(name) as clusters FROM clusters GROUP BY c_id) AS clusters ON countries.id = c_id
WHERE countries.id = 2
ORDER BY events.year_1 ASC
LIMIT 30
LEFT JOIN (SELECT countries.id, event_to_country.event_id, countries.name as countries FROM countries LEFT JOIN event_to_country ON countries.id = event_to_country.country_id) as countries ON events.id = countries.event_id
LEFT JOIN countries ON events.country_id = countries.id
я как раз про это и говорил - возвращает пусто