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SELECT 
  lang.name, 
  lang.value 
FROM 
  cscart_language_values lang 
WHERE 
  lang.lang_code = 'vn' 
  AND lang.name IN (
    'click_here_for_refer_by_mail', 
    'click_here_for_refer_by_mail', 
    'click_here_for_refer_by_mail', 
    'click_here_for_refer_by_mail'
  )

Query time 0.00028

JSON explain

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