SELECT 
  lang.name, 
  lang.value 
FROM 
  cscart_language_values lang 
WHERE 
  lang.lang_code = 'es' 
  AND lang.name IN (
    'storefront_search_general', 'search_products', 
    'storefront_search_button', 'storefront_search_button', 
    'storefront_search_general', 'search_products', 
    'storefront_search_button', 'storefront_search_button'
  )

Query time 0.00044

JSON explain

{
  "query_block": {
    "select_id": 1,
    "nested_loop": [
      {
        "table": {
          "table_name": "lang",
          "access_type": "range",
          "possible_keys": ["PRIMARY"],
          "key": "PRIMARY",
          "key_length": "392",
          "used_key_parts": ["lang_code", "name"],
          "rows": 3,
          "filtered": 100,
          "index_condition": "lang.lang_code = 'es' and lang.`name` in ('storefront_search_general','search_products','storefront_search_button','storefront_search_button','storefront_search_general','search_products','storefront_search_button','storefront_search_button')"
        }
      }
    ]
  }
}