Buffett bought more and more falling stocks, may indicate that he believes that these two stocks are what he calls "quality merchandises"

$Occidental Petroleum(OXY.US)$ $Chevron(CVX.US)$
Buffett has bought on bargain hunting more than once. About the market downturn, he once said "whether we're talking about socks or stocks, I like buying quality merchandise when it is marked down." .
Buffett bought Occidental Petroleum Corp's shares on a large scale from March to May this year, making it the sixth largest heavy stock of Berkshire. During June 17-22, he bought another 9.55 million shares of Occidental Petroleum Corp's shares. However, since June, Occidental Petroleum Corp's shares have fallen sharply, with a cumulative decline of 19.5%.
In addition, Buffett also holds Chevron, another leading stock in the crude oil industry , which is currently ranked as the fourth largest heavy stock of Berkshire. Since June, Chevron has also fallen sharply, with a cumulative decline of 15.3%.
On June 22, US Eastern time, international crude oil futures prices and US oil related sectors fell sharply. Occidental Petroleum Corp and Chevron fell 3.63% and 4.35% respectively.
Although both stocks fell more than 15%, Buffett is still buying more. This may indicate that Buffett believes that these two stocks are what he calls "quality merchandises".