So far, trying to make sense of the ageing process, he'd been working with yeast.至今，他仍在研究酵母以试着了解衰老过程

so far:迄今为止；到某个程

It's the hottest day I've had so far.

这是迄今为止我经历的最热的一天。

I can help you in so far as I can.

我会尽力去帮助你的。

make sense of:懂得； 了解 ... 的意义

Can you make sense of what I say?

你能领会我说的意思吗？

the goal about fifteen years ago was to find out why do they age, and what can we do about it?15年前的目标是找出它们衰老的原因，我们又能为其做什么

find out:发现；找出来；揭发

I must find out which of them was in the right.

我一定要搞清楚他们当中谁有理。

He was at pains to find out the truth.

他尽力了解事实真相。