For the next times, you should try to book the ticket with a long overnight layover at AMS. If it is <24h, it is not considered a stopover and thus the fare remains the same, but it will grant you the possibility to request a shortcheck of your bags to AMS.
For this booking, do note that if you book a CDG-LHR flight with AF, KL agents at PEK should be able to check your bags through to LHR. It will allow you a more convenient transit at CDG, though if one of your flight is delayed and you miss the connection to LHR you may not be protected...