what to buy during recession and market down time?

It has been another crazy week.

DJIA 8852
Nasdaq 1711
S&P500 940
Russell2000 526

All YTD falled more than 30% so far!

Its extremely volatile these day.
This is a traders market.
As for long term investor, unless you have good cash flow, in which you do not need the money in the next few years, you should stay away, until the SPX is above moving average of 200day.

However, the 2nd richest man of the world, said otherwise : Buy America, I am.

"A simple rule dictates my buying: Be fearful when others are greedy and be greedy when others are fearful," Buffett, 78, said in an opinion piece published Friday in The New York Times.

If so, what to buy? Anyone know what business, industry will do well and grow during recession?