LONDON -- One of Warren Buffett's famous investing sayings is "Be fearful when others are greedy and greedy only when others are fearful." In other words, sell when others are buying and buy when they're selling.

But we might expect Foolish investors to know that, so looking at what Fools have been buying recently might well provide us with some ideas for good investments.

So, in this series of articles, we're going to look at what customers of The Motley Fool ShareDealing Service have been buying in the past week or so and what might have made them decide to do so.

A 50% discount
At No. 8 in the latest "Top 10 Buys" is Kazakhmys (LSE:KAZ), the Kazakhstan copper mining company. (Based on aggregate data from The Motley Fool ShareDealing Service.) On the face of it, it doesn't seem an immediately appealing prospect. Its share price is down more than 66% since it floated in 2005, and it's lost a whopping 33% of its value this year alone.

But perhaps that was the attraction. At its current price, Kazakhmys appears to be on a discount of about 50% to its tangible net asset value (TNAV), which ought to provide some reassurance of downside protection. Furthermore, Kazakhmys has plans to bring two new mines online by 2015, which would increase its production by over 50%, albeit at a cost of 2.5 billion pounds. If copper prices rise, the share price could well do likewise. But a lot could happen between now and 2015, and if the price of copper falls...

Buying Kazakhmys also gets you an indirect investment in another FTSE 100 company, the natural resources group Eurasian Natural Resources Corporation (ENRC), in which Kazakhmys has a 26% stake. However, that may not be a good thing, considering ENRC's own dreadful performance since its flotation in 2007 and the questions surrounding its corporate governance and certain business activities (questions asked by both the Financial Services Authority and Serious Fraud Office, no less).

Kazakhmys's stake in ENRC lost more than half its value over the course of 2012, which serves to reduce its discount to TNAV to about 30%, and it recently announced that it may have to consider an impairment. But that will have to wait until after ENRC's full-year results on March 20. Shareholders, old and new, will therefore be awaiting Kazakhmys's preliminary full-year results on March 26 with keen interest.

A high-quality growth share
If you're looking for a high-quality growth share, you'll want to get hold of "The Motley Fool's Top Growth Share for 2013," the latest report by the Fool's expert analysts and has only just been released.

It's completely free of charge, but like all special reports from the Fool, it will only be available for a limited period, so get your copy delivered to your inbox now!