SELECT 
  cscart_product_descriptions.product_id, 
  cscart_product_descriptions.meta_keywords, 
  cscart_product_descriptions.meta_description, 
  cscart_product_descriptions.search_words, 
  cscart_product_descriptions.promo_text, 
  cscart_product_descriptions.unit_name 
FROM 
  cscart_product_descriptions 
WHERE 
  cscart_product_descriptions.product_id IN (
    3178, 3188, 3196, 3274, 3276, 3285, 3286, 
    3290, 3292, 6744, 6749, 6760, 6767, 
    6824, 6833, 6840, 7278, 7351, 7353, 
    7355, 7357, 7359
  ) 
  AND cscart_product_descriptions.lang_code = 'en'

Query time 0.00081

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "26.50"
    },
    "table": {
      "table_name": "cscart_product_descriptions",
      "access_type": "range",
      "possible_keys": [
        "PRIMARY",
        "product_id"
      ],
      "key": "PRIMARY",
      "used_key_parts": [
        "product_id",
        "lang_code"
      ],
      "key_length": "9",
      "rows_examined_per_scan": 22,
      "rows_produced_per_join": 22,
      "filtered": "100.00",
      "index_condition": "((`gaseus`.`cscart_product_descriptions`.`product_id` in (3178,3188,3196,3274,3276,3285,3286,3290,3292,6744,6749,6760,6767,6824,6833,6840,7278,7351,7353,7355,7357,7359)) and (`gaseus`.`cscart_product_descriptions`.`lang_code` = 'en'))",
      "cost_info": {
        "read_cost": "24.30",
        "eval_cost": "2.20",
        "prefix_cost": "26.50",
        "data_read_per_join": "100K"
      },
      "used_columns": [
        "product_id",
        "lang_code",
        "meta_keywords",
        "meta_description",
        "search_words",
        "promo_text",
        "unit_name"
      ]
    }
  }
}

Result

product_id meta_keywords meta_description search_words promo_text unit_name
3178
3188
3196
3274
3276
3285
3286
3290
3292
6744
6749
6760
6767
6824
6833
6840
7278
7351
7353
7355
7357
7359