There are one-hit wonders, and then there are those stocks for which the initial big move is only a preview for even bigger and better gains to come.

Today, we list a pair of stocks that made some of the biggest upward moves over the past month, despite the incredible volatility in the market, which we'll pair with the ratings issued by our Motley Fool CAPS community. The higher each stock's rating, the greater CAPS members' faith in that company's ability to keep on beating the market.

Stock

1-Month Change

CAPS Rating
(out of 5)

Human Genome Sciences (Nasdaq: HGSI) 80.8% **
Feihe International (NYSE: ADY) 75.9% **

Source: FinViz.com; 1-month change from Feb. 8 to March 9.

While you were out, the markets rebounded, but they may turn tail again if Europe's fragile financial system falls apart. So before we get shaken out again, let's see what the CAPS community thinks about these stocks.

A mighty temblor
Sure, someone else might come along and offer a better price for Human Genome Sciences, but pharmaceutical giant GlaxoSmithKline (NYSE: GSK), which is making a hostile bid for the biotech, says it doesn't make sense for anyone else to buy it. GSK already has the rights to HGS' three main assets and the 81% premium it was offering was already sweet enough without having to offer more. Just because HGS is trading at half its 52-week high -- post-bid -- doesn't mean Glaxo has to add more honey to the pot.

If Glaxo did "lowball" the offer, it's because it's dealing from a position of strength. While HGS' shares have been trading above GSK's $13 offer in an indication they believe someone else will bid higher, analysts think there may be no white knight riding to the rescue because GSK has such deep insight into its drug pipeline.

Yet GSK needs HGS, too, particularly lupus therapy Benlysta, which, although it currently has lackluster sales, analysts still expect will become a $1 billion blockbuster. Glaxo missed analyst expectations this past quarter and with a particularly steep drop off the patent cliff looming, having backup is essential.

I've rated Human Genome Sciences to underperform the market on CAPS because if the deal goes through, it will be at GSK's $13 offer and if it doesn't, the stock will crater again. But tell me in the comments section below whether you think there will be a white knight riding to the rescue, then add Human Genome Sciences to your watchlist to see how it plays out.

Whistling dairy
It could be a halo effect that's driving shares of Chinese milk formula maker Feihe International higher. Nestle recently agreed to pay nearly $12 billion for the baby food business of Pfizer (NYSE: PFE), more than the $10 billion analysts anticipated.

Pfizer generated $2.4 billion in sales from its nutrition division last year, and 85% of those sales came from emerging markets -- 25% in China alone. That has people looking at Danone, Mead, and Abbott Labs (NYSE: ABT), which is looking to calve off its nutrition division, but to suggest Feihe could similarly benefit might be a bit of a stretch.

Chinese baby formula producers have been wracked by scandal, though American Dairy -- what Feihe was formerly called -- escaped the melamine debacle that hit the industry hard. That hasn't made its performance any better, though it managed to report an operating profit in 2011 even if it still had net losses, narrower though they were. The domestic industry is still eyed suspiciously, which is why Pfizer and others view the market as such a big opportunity.

It might be early innings to say that Feihe has made a definitive turnaround, but CAPS member rogisi is hoping it's true. Add the milk maker to the Fool's free portfolio tracker and tell us on the Feihe International CAPS page if you think it will be able to milk profits going forward.

Shake, rattle, and roll
These two stocks shook the market this past month, but the Fool has found one company that's digging up massive profits and is likely to continue to do so if the markets become rattled. Roll on over to get your free copy, but hurry, because it's available only for a limited time.