[one interpretation of Oppenheimer:] There are an awful lot of true things. The ones that we know might not be the most useful, but they are the ones that happen to lie in the (extremely small?) subset of true things that humans are capable of understanding.

Quibble: Two things you might have missed:

• Oppenheimer was talking about "deep things in science", not about "truths."
• He said "possible to find them", not "possible to understand them".