成员的完整列表，这些成员属于 NIMQChatSearchMsgByPageParam,包括所有继承而来的类成员

	channelId	NIMQChatSearchMsgByPageParam
	cursor	NIMQChatSearchMsgByPageParam
	fromAccount	NIMQChatSearchMsgByPageParam
	fromTime	NIMQChatSearchMsgByPageParam
	includeSelf	NIMQChatSearchMsgByPageParam
	keyword	NIMQChatSearchMsgByPageParam
	limit	NIMQChatSearchMsgByPageParam
	msgTypes	NIMQChatSearchMsgByPageParam
	order	NIMQChatSearchMsgByPageParam
	serverId	NIMQChatSearchMsgByPageParam
	sortType	NIMQChatSearchMsgByPageParam
	subTypes	NIMQChatSearchMsgByPageParam
	toTime	NIMQChatSearchMsgByPageParam