SELECT 
  cscart_product_descriptions.product_id, 
  cscart_product_descriptions.short_description, 
  IF(
    cscart_product_descriptions.short_description = '', 
    cscart_product_descriptions.full_description, 
    ''
  ) AS full_description, 
  cscart_product_descriptions.meta_keywords, 
  cscart_product_descriptions.meta_description, 
  cscart_product_descriptions.search_words, 
  cscart_product_descriptions.promo_text 
FROM 
  cscart_product_descriptions 
WHERE 
  cscart_product_descriptions.product_id IN (
    1029131, 1029075, 1028783, 1051342, 
    1051499, 1029173, 1028496, 1051407, 
    1029127, 1032879, 1051420, 1029100, 
    1051411, 1028475, 1051509, 1028753, 
    1029112, 1028738, 1032919, 1051341, 
    1051343, 1028600, 1032891, 1028545, 
    1029184, 1028719, 1032924, 1028464, 
    1028517, 1028727, 1028541, 1028792, 
    1028734, 1032904, 1032863, 1029178
  ) 
  AND cscart_product_descriptions.lang_code = 'ro'

Query time 0.00159

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "43.19"
    },
    "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": 36,
      "rows_produced_per_join": 36,
      "filtered": "100.00",
      "cost_info": {
        "read_cost": "39.59",
        "eval_cost": "3.60",
        "prefix_cost": "43.19",
        "data_read_per_join": "137K"
      },
      "used_columns": [
        "product_id",
        "lang_code",
        "short_description",
        "full_description",
        "meta_keywords",
        "meta_description",
        "search_words",
        "promo_text"
      ],
      "attached_condition": "((`maniamall_cscart`.`cscart_product_descriptions`.`product_id` in (1029131,1029075,1028783,1051342,1051499,1029173,1028496,1051407,1029127,1032879,1051420,1029100,1051411,1028475,1051509,1028753,1029112,1028738,1032919,1051341,1051343,1028600,1032891,1028545,1029184,1028719,1032924,1028464,1028517,1028727,1028541,1028792,1028734,1032904,1032863,1029178)) and (`maniamall_cscart`.`cscart_product_descriptions`.`lang_code` = 'ro'))"
    }
  }
}

Result