To be in dire distress or to struggle greatly—having a hard time facing problems or difficulties (often used as 'shikuhakku suru').
引っ越しの手続きで四苦八苦したが、何とか終わった。
I had a lot of trouble with the moving procedures, but I managed to finish them somehow.
新入社員は仕事を覚えるのに四苦八苦している。
The new employee is struggling a lot to learn the job.
予算が足りず、プロジェクトは四苦八苦している。
With insufficient budget, the project is having a hard time.
In Buddhism, the concept of the four and eight kinds of suffering (such as birth, aging, illness, death, separation from loved ones, meeting with disliked persons, not getting what one wants, and the afflictions of the five skandhas).
お寺の法話で四苦八苦について説明があった。
There was an explanation about the four and eight sufferings in the temple sermon.