SELECT 
  cscart_products.* 
FROM 
  cscart_products 
WHERE 
  cscart_products.product_id IN (
    46737, 46781, 46782, 46783, 46784, 46785, 
    46786, 46787, 46788, 46789, 46790, 
    46791, 46792, 46793, 46794, 46795
  )

Query time 0.00099

JSON explain

{
  "query_block": {
    "select_id": 1,
    "nested_loop": [
      {
        "table": {
          "table_name": "cscart_products",
          "access_type": "range",
          "possible_keys": ["PRIMARY"],
          "key": "PRIMARY",
          "key_length": "3",
          "used_key_parts": ["product_id"],
          "rows": 16,
          "filtered": 100,
          "index_condition": "cscart_products.product_id in (46737,46781,46782,46783,46784,46785,46786,46787,46788,46789,46790,46791,46792,46793,46794,46795)"
        }
      }
    ]
  }
}