NEW YORK (TheStreet) -- Jim Cramer sees a lot more in Alcoa's (AA) - Get Report earnings than how the aluminum producer is doing.

Cramer said Thursday the reason investors need to pay attention to Alcoa's earnings, released late Wednesday, is because the company is in so many different industries, it is a good indicator for the health of many companies ahead of their own earnings.

Cramer said Alcoa's actual earnings are becoming more skewed to highly finished products but "what you need to know is how their end markets are doing."

For instance, Alcoa's U.S. truck numbers show the high demand for trucks domestically; its strong turbines results mean that natural gas-burning turbines are being used by utilities instead of coal.

So where do you invest? "When you look at the auto build" from Alcoa, "you want to find domestic autos," Cramer said. That means don't look to companies that make auto parts but to companies likeAutoZone (AZO) - Get Report or O'Reilly Automotive (ORLY) - Get Report that sell these auto parts.

What else does he like? Snap-on Incorporated (SNA) - Get Report, the tool maker, and companies that are "uniquely domestic" including Stanley Black & Decker (SWK) - Get Report, which he considers a buy; and Mohawk Industries (MHK) - Get Report, the Georgia-based flooring company. However, he wants you to sell anything associated with coal including railroads stocks.

Another read off Alcoa: beer. Cramer said that "beer sales are very strong'' based on Alcoa's packaging numbers. So look to Constellation Brands (STZ) - Get Report, Anheuser-Busch Inbev (BUD) - Get Report or Molson Coors Brewing Company (TAP), although he admitted Molson "hasn't done much recently."

At the time of publication, Jim Cramer's charitable trust Action Alerts PLUS held no positions in stocks mentioned.