SELECT 
  cscart_products.* 
FROM 
  cscart_products 
WHERE 
  cscart_products.product_id IN (
    12954, 12955, 12947, 12949, 12946, 12948, 
    12956, 17725, 17726, 17727, 17728, 
    17729, 17730, 17731, 17732, 12958, 
    12960, 12959, 12962, 12964
  )

Query time 0.00075

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "table_name": "cscart_products",
      "access_type": "range",
      "possible_keys": ["PRIMARY"],
      "key": "PRIMARY",
      "key_length": "3",
      "used_key_parts": ["product_id"],
      "rows": 20,
      "filtered": 100,
      "index_condition": "cscart_products.product_id in (12954,12955,12947,12949,12946,12948,12956,17725,17726,17727,17728,17729,17730,17731,17732,12958,12960,12959,12962,12964)"
    }
  }
}