Here and there; sparsely; in twos or threes — describes things appearing scattered or thinly distributed.
春になると庭に花がちらほら咲く。
In spring, flowers bloom here and there in the garden.
会場にはまだ人がちらほらいるだけだった。
There were only a few people scattered around the venue.
書店の棚に新刊がちらほら並んでいた。
New releases were sparsely lined up on the bookstore shelves.
Now and then; occasionally — used for events that happen intermittently and infrequently.
この地域では冬に雪がちらほら降ることがある。
In this area, it sometimes snows lightly in winter.
彼は会議にちらほら顔を出す程度だ。
He only shows up to meetings now and then.
仕事の合間にちらほらメールをチェックする。
I check my email occasionally between tasks.