Customers can also improve future shopping experiences by filing complaints to the retailer, instead of complaining to the rest of the world.
分析主干：Customers can also improve experiences
1.介词by 后面动名词短语filing...作宾语，表示手段或方式。instead of...短语引导的内容相当于filing 的转折并列成分。
2.注意动词filing(不是filling)，意思是 正式提出 。
译文：消费者也可以采取措施改善以后的购物体验。他们可以直接向商家投诉，而不是到处散布自己不愉快的经历。