Not all surprises are good ones, unfortunately. Over the last couple of weeks, we've looked at some highly regarded stocks that delivered lousy returns over a 30-day period. Today, we'll consider another batch of these outstanding underachievers (click here and here for previous articles).

For some folks, like the team over at Motley Fool Inside Value, it's not all bad when good companies stumble. If stocks like the ones below fall by anywhere from 9% to 27% over a short period of time, they might become attractive buying opportunities for investors. The key is for investors to separate the value plays from the value traps.

The table below was created with data from our new Motley Fool CAPS stock-picking service. Our community gave these stocks its highest five-star rating a mere 30 days ago, only to see them deliver woeful short-term returns:

Stock

30-day return

One-year return

Charles & Colvard (NASDAQ:CTHR)

(26.69%)

(54.46%)

Aspreva Pharmaceuticals (NASDAQ:ASPV)

(23.65%)

46.98%

Intermec (NYSE:IN)

(20.33%)

(31.27%)

Sanderson Farms (NASDAQ:SAFM)

(19.45%)

(21.93%)

VitalStream Holdings (NASDAQ:VSTH)

(14.37%)

N/A

GOL Linhas Areas Inteligentes (NYSE:GOL)

(8.69%)

80.80%

Data provided from Motley Fool CAPS as of Oct. 24.

Intermec, Sanderson Farms, and VitalStream Holdings have all been demoted as a result of this recent performance; they're now two-star stocks. Charles & Colvard and GOL Linhas Areas Inteligentes have managed to retain their five-star ratings, however, despite a tough month. Perhaps these two stocks are attractive candidates for further due diligence.

Charles & Colvard is a global seller of moissanite jewelry. Yeah, I didn't know what moissanite jewelry was either. Apparently, it's jewelry that looks like a diamond, but costs only a fraction as much for consumers. According to our CAPS community, the company has a strong competitive advantage and a satisfied and growing customer base. The outlook for the company over the next five years seems to be favorable. It even has former Duchess of York Sarah "Fergie" Ferguson promoting moissanite jewelry on its website.

Our community has awarded Charles & Colvard 43 "outperform" ratings and zero "underperforms." GOL Linhas Areas Inteligentes, a low-cost Brazilian airline that our community thinks has strong growth potential, has an equally bullish rating. 55 community members have rated it an "outperform," and only one member has rated it negatively.

Do you think either of these companies warrants further research? Come join us over at CAPS to learn more about what our community thinks. We've already signed up almost 11,500 investors, and our aim is to create the world's best stock-picking service. If you're looking for great stock ideas, this is the place to be. Click here to get in the game. It's entirely free to do so.

For additional value stock ideas, give Motley Fool Inside Value a try, free for 30 days.

Fool editor John Reeves does not own shares in any of the companies mentioned in this article. He did, however, rate Charles & Colvard an outperform on CAPS just a few minutes ago. Sanderson Farms was once a Stock Advisor pick. The Fool is investors writing for investors.