Additional resignations from President Donald Trump's administration is one potential catalyst for a stock pullback, closely followed strategist Bob Doll said Monday.

"My view is corrections are non-predictable and random but after the fact we always know why," said Doll, Nuveen Asset Management's chief equity strategist.

"Catalysts could be maybe earnings aren't as good as we think. Maybe some adults leave the Trump administration. Maybe inflation as we saw a hint of the Friday employment report and wages begin to move higher," Doll added in an interview on CNBC's "Worldwide Exchange."

Doll said earnings have acted as a stimulus for the stock market's rise to new record highs so far this year, and he doesn't see why that should stop.

"Earnings should be reasonably good along with economic statistics," he said. "We've got, of course, that hurricane effect we saw in the jobs report last Friday. That could affect some earnings. It could be the right excuse when companies don't make it."

Stocks were up modestly in early trading Monday, despite Friday's jobs numbers, which revealed a decline in nonfarm payrolls for September due to the havoc inflicted by Hurricanes Harvey and Irma. It was the first monthly decline in seven years.

Investors should stick with sectors that have done well because of earnings, Doll suggested.

"We're seeing improvement in financials," he said. "Selected tech — I don't think it's just a blanket. Health care still has a good tail wind in terms of earnings, and valuations are not horribly stretched."