Sandbox

SELECT 
  cscart_dosiin_category_descriptions.*, 
  cscart_dosiin_categories.*, 
  cscart_seo_names.name as seo_name, 
  cscart_seo_names.path as seo_path 
FROM 
  cscart_dosiin_categories 
  LEFT JOIN cscart_dosiin_category_descriptions ON cscart_dosiin_categories.category_id = cscart_dosiin_category_descriptions.category_id 
  AND cscart_dosiin_category_descriptions.lang_code = 'en' 
  LEFT JOIN cscart_seo_names ON cscart_seo_names.object_id = cscart_dosiin_categories.category_id 
  AND cscart_seo_names.type = 'u' 
  AND cscart_seo_names.dispatch = '' 
  AND cscart_seo_names.lang_code = 'en' 
WHERE 
  cscart_dosiin_categories.category_id = 120

Query time 0.00931

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}