In this mailbag segment of the Market Foolery podcast, host Chris Hill and senior analyst Matt Argersinger analyze what's going on with China's major foreign-listed tech giants, which have lost value in 2018 even though their fundamentals appear to be positive.From the Fools' point of view, it's a combination of factors plaguing Alibaba (NYSE: BABA), Baidu (NASDAQ: BIDU) and JD.com (NASDAQ: JD), among others: the trade war, decelerating economic growth in China, and large institutions cashing out of Chinese stocks.