This is the 5387th most frequent Korean word.
들면서
"While lifting" or "while entering."
In this sentence, '들면서' is used conjunctively indicating the simultaneity of aging and the discovery of new hobbies.
나이를 먹어가 들면서 새로운 취미를 찾았다.
As I grew older, I found a new hobby.
In this case, '들면서' describes the passage of time concurrently with the act of memories becoming vivid.
시간이 흐르들면서 옛 추억들이 더욱 생생해졌다.
As time passed, old memories became more vivid.
Here, '들면서' connects the action of sunlight brightening with the intensification of the green color on the trees, showing two events occurring in parallel.