SELECT 
  cscart_products.* 
FROM 
  cscart_products 
WHERE 
  cscart_products.product_id IN (
    10370, 10372, 10374, 10376, 10377, 10378, 
    10379, 10380, 10381, 10371, 10373, 
    10375, 12944, 15781, 12853, 12854, 
    12855, 12856, 12551
  )

Query time 0.00061

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": 19,
      "filtered": 100,
      "index_condition": "cscart_products.product_id in (10370,10372,10374,10376,10377,10378,10379,10380,10381,10371,10373,10375,12944,15781,12853,12854,12855,12856,12551)"
    }
  }
}