I want you to dig deep. Find out who she is and where she came from.我想让你彻底调查一下, 弄清她是谁, 从哪里来。

You don't need to dig deep for hidden meanings.你无需细究言外之意。

She had to dig deep to find the strength to catch her rival on the final straight.她不得不拼尽全力以在最后一段直道上追上对手。

We dug deep to hang onto our lead through the last ten minutes.我们在最后10分钟竭尽全力保持领先地位。