SELECT 
  lang.name, 
  lang.value 
FROM 
  cscart_language_values lang 
WHERE 
  lang.lang_code = 'zh' 
  AND lang.name IN (
    'sg_ew.manual', 'sg_ew.warranty_coverage', 
    'sg_ew.manufacturer_warranty', 
    'sg_ew.years', 'sg_ew.extension', 
    'sg_ew.years', 'sg_ew.warranty_duration', 
    'sg_ew.plan_price', 'sg_ew.add_plan', 
    'sg_ew.add_plan', 'sg_ew.manual', 
    'sg_ew.warranty_coverage', 'sg_ew.manufacturer_warranty', 
    'sg_ew.years', 'sg_ew.extension', 
    'sg_ew.years', 'sg_ew.warranty_duration', 
    'sg_ew.plan_price', 'sg_ew.add_plan', 
    'sg_ew.add_plan'
  )

Query time 0.00024

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost": 0.01470144,
    "nested_loop": [
      {
        "table": {
          "table_name": "lang",
          "access_type": "range",
          "possible_keys": ["PRIMARY"],
          "key": "PRIMARY",
          "key_length": "392",
          "used_key_parts": ["lang_code", "name"],
          "loops": 1,
          "rows": 8,
          "cost": 0.01470144,
          "filtered": 100,
          "attached_condition": "lang.lang_code = 'zh' and lang.`name` in ('sg_ew.manual','sg_ew.warranty_coverage','sg_ew.manufacturer_warranty','sg_ew.years','sg_ew.extension','sg_ew.years','sg_ew.warranty_duration','sg_ew.plan_price','sg_ew.add_plan','sg_ew.add_plan','sg_ew.manual','sg_ew.warranty_coverage','sg_ew.manufacturer_warranty','sg_ew.years','sg_ew.extension','sg_ew.years','sg_ew.warranty_duration','sg_ew.plan_price','sg_ew.add_plan','sg_ew.add_plan')"
        }
      }
    ]
  }
}