SELECT 
  cscart_products.* 
FROM 
  cscart_products 
WHERE 
  cscart_products.product_id IN (
    6764, 6729, 6768, 6718, 6720, 6719, 6717, 
    6767, 6721, 6765
  )

Query time 0.00026

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": 10,
      "filtered": 100,
      "index_condition": "cscart_products.product_id in (6764,6729,6768,6718,6720,6719,6717,6767,6721,6765)"
    }
  }
}