If you're looking to maximize your returns, now is a great time to buy stocks. Many stocks are trading at very low valuations and there's a lot of room for them to rise in value over the long term. It may be unnerving to buy during a bear market, but that's when investors can grab some of the best bargains. Below are two stocks that are not just cheap buys, but also stocks that could double in value.

1. Tilray

Cannabis company Tilray (TLRY) is down more than 90% in just the past year. That's significantly worse than the Horizons Marijuana Life Sciences ETF (HMLSF -9.94%) which has crashed 75%, or the S&P 500, which is down just 12% during that time. It's currently trading at about $9 per share. For Tilray to double in value would mean getting back to the price it was at in February before investors learned of the seriousness of the coronavirus.

The coronavirus pandemic is affecting businesses and hurting sales. But cannabis is one of the things that consumers are stockpiling, as they worry they may not have access to it if there's a lockdown. The good news for British Columbia-based Tilray is that some provinces in Canada have already designated cannabis stores as essential. Both Ontario and Quebec, two of the largest provinces in the country, have said that cannabis businesses will be able to continue operating even as the government forces other businesses to shut down in the hopes of containing COVID-19.

Not all provinces have made decisions on whether cannabis stores will remain open, but for pot stocks like Tilray, it's a good sign that in two big markets like Quebec and Ontario, pot shops can continue operating.

Marijuana store sign.

Image source: Getty Images.

Another reason that Tilray's struggling: It released its year-end financials on March 3, which disappointed investors, with an impairment loss of $112 million weighing down the company's bottom line. Although annual revenue of $167 million was nearly quadruple the prior-year tally of $43 million, Tilray reported a mammoth $321 million net loss. That was nearly five times the $68 million loss it incurred in 2018. But Tilray's been cutting costs; in February, the company laid off about 10% of its workforce as it looks to improve its bottom line.

With cannabis sales up in recent weeks in both Canada and the U.S., there's an opportunity for pot stocks to post some better-than-expected results this year. And Tilray's one of the better deals out there. The stock is currently trading at a price-to-sales ratio of about 3, which is a very modest valuation compared to the more than 20 and even 100 times revenue it's traded for in the past.

There's ample room for Tilray's stock to soar on some improved results this year, and it could be a good, calculated risk for investors to take today.

2. Boeing

Boeing (BA -0.26%) is a risky buy, like Tilray. Things haven't been going well for the airline stock over the past year. Multiple deadly crashes involving the company's 737 MAX jets have forced Boeing to suspend their production. And now, the coronavirus pandemic is keeping people indoors and having a widespread effect on the travel industry as a whole.

In the past 12 months, shares of Boeing have fallen 66%, with the stock coming off new 52-week lows. It's not an easy time to invest in Boeing, but that's precisely why it may be an excellent time to do so. Despite the adversity in the industry, billionaire investor Warren Buffett has recently said he wouldn't be selling the airline shares that he owns, saying that the coronavirus "won't stop the progress of the country or the world." . Boeing isn't one of his holdings, but his words are an important reminder that as bad as the coronavirus may seem today, the economy will recover from it.

And there's reason to be optimistic about Boeing's 737 MAX jets as well, as the company stated that it could resume production of them as early as May. While it'll be a long road to recovery for both the 737s and Boeing, for investors, the payoff could be significant.

Management is doing what it can to strengthen its financials and gear up for what could be a very challenging year in 2020. Boeing recently announced that it would suspend its dividend as a result of the coronavirus and cancel CEO pay as well. It's a dark time for Boeing, but for Foolish investors, the time could be ripe to buy Boeing and stake out a good position today. It may take multiple years for the stock to get back to where it was before all these headwinds, but buying shares of Boeing today could prove to be a steal of a deal.