Select Japanese and European equities hold the greatest potential right now, Morningstar's Fund Manager of the Decade said Wednesday.

On CNBC's "Halftime Report," Harris Associates CIO David Herro said that it was important to focus on undervalued multinational companies in lackluster economies.

"These European businesses, most or many of what we own, really, they're domiciled in Europe, but they're global companies. They have business all over the world, and they're actually doing quite well," he said. "You see companies like Allianz and Daimler, even BMW and Diageo, these are big global businesses. And because they're based in Europe and people are kind of down on Europe, the share prices have been weak and value's been strong.

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"So, we really look at companies, not where they're based but where they earn money. And this is a way to take advantage of the situation because everyone's fleeing the macro story of Europe, but what they're missing is the micro. They're missing these companies are making good money around the world."

Herro manages the Morningstar five-star-rated Oakmark International Fund, which has a five-year return of 72 percent.

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A weak euro and Japanese would further boost companies in those regions, he added.

"These are going to be good for European multinationals, for Japanese multinationals and less good for U.S. multinationals," he said. "So, the big blue chip names like a Toyota, like a Honda, like a Daiwa Securities, these have been ignored by the market, and their valuations are starting to look very compelling, especially when you look at what's happening with the Japanese yen."

—By CNBC's Bruno J. Navarro