Lehmann attacked Broad for not walking during the first Ashes test at Trent Bridge last month in an interview with an Australian radio station, for which he was fined 20 percent of his match fee by the International Cricket Council.
He accused Broad of "blatant cheating" and called on Australia's fans to send the fast bowler home from the return Ashes series in tears.
"I've had a chat with him already. We just move on," Lehmann told Sky Sports on Monday.
"It was a good learning curve for a new coach, wasn't it? You know, it was a jovial setting but you've got to learn from that. I've got to learn and improve from that.
"The players aren't on their own in trying to improve. Coaches have got to improve so that's something I've got to get better at."
Broad had edged a ball from spinner Ashton Agar that was caught by Michael Clarke, via wicketkeeper Brad Haddin's gloves, but did not walk after umpire Aleem Dar gave him not out.
Australia had already used up all their reviews so were unable to challenge the decision, and Broad later admitted hitting the ball.
Meanwhile Lehmann said they were likely to have a more settled batting lineup for the return series, which begins in Brisbane on November 21.
The selectors had come under fire for regularly changing the top seven during the series, which England won 3-0, with Shane Watson batting as an opener and at numbers three, four and six at various stages.
"When we get our side for the first test match, our batting seven, that will be the side for the first couple at least," Lehmann said.
"We'll be pretty settled in Australia, knowing the conditions really well."
(Reporting by Josh Reich; editing by Toby Davis)
