Jim Cramer loves to take calls on "Mad Money" from investors who want his opinion on stocks. But he is only human, and sometimes he gets stumped.
When that happens, Cramer goes back to the drawing board to do his homework and then circles back to opine.
"It is a good exercise in teaching you about how to analyze stocks that you might not know about," the "Mad Money" host said.
The first stock was NovoCure, which Cramer was familiar with, but wanted to refresh his memory before declaring a verdict. NovoCure developed a potentially revolutionary way to fight cancer with a proprietary technology known as Tumor Treating Fields, where it uses low-intensity electrical fields that disrupt key molecules within cancer cells and prevents cancer cells from replication.
And unlike many early stage biotechs, NovoCure has the clinical data, regulatory approvals and real world experience to make the technology work. The issue with the stock was that it came public at a bad time, with an IPO back in October, when all things biotech were abhorred.
But with health care suddenly back in favor on Wall Street and an increase in M&A activity, Cramer thinks this could be a great stock for speculation. Not for a retirement account, just for speculation.
Read more from Mad Money with Jim Cramer
The next stock that stumped Cramer was Ollie's Bargain Outlet, which is an off-price retailer that sells brand name merchandise at a 70 percent discount versus what a shopper would pay at a department store.
Ollie's reported on Wednesday and delivered a strong top and bottom line beat, including 5 percent same-store sales growth and fantastic full year earnings guidance.
"This could be the kind of regional and national growth story that money managers get very excited about," Cramer said.
However, Cramer was concerned that Ollie's came public last July with a private equity backed IPO. The private equity company behind it, CCMP Capital Advisors, still own 59 percent of the company. That could mean CCMP is the one in control, and its interests will come first ahead of regular shareholders.
Cramer also found that that the stock was very expensive compared to competitors such as TJX and Dollar General. Still, the company is clearly executing and is an up and coming growth story. Cramer recommended waiting for a pullback before pulling the trigger.
The last stock Cramer highlighted was NeoPhotonics, a supplier of fiber-optic components for high-speed communications networks. Ever since the stock bottomed in August, 2014, it has been on fire. In fact, the stock is up 30 percent just for the year.
"If you want to speculate on optical equipment, then NeoPhotonics might be the way to go, but please, I'm begging you, wait for the stock to get hit before you consider doing any buying," Cramer said.