可以用 "as much as possible" 或 "to the greatest extent possible" 来表示 "尽可能多"。
这些短语都是由 "as + 形容词/副词 + as possible" 或 "to the + 形容词/副词 + extent possible" 构成的。
例句：
I'm trying to save as much money as possible. (我正在尽量省钱。)
We need to finish this project to the greatest extent possible. (我们需要尽可能完成这个项目。)