It's not that he can't rescue Zhou Jiajia, but rather that he's uncertain whether Zhou Jiajia will still be here.
After all, he caused a big stir more than a year ago and again now, so the Bloodsucking Sect must be on guard against him.
Regardless of whether the Bloodsucking Sect has shifted their base, since he's here, he should search the place from top to bottom. If he finds it's deserted, then he'll go look elsewhere.
Thus, he begins to step into a railway tunnel, entering the interior of the Bloodsucking Sect.
The sect is built beneath a large mountain range, the environment is dark and the terrain is complex, making it easy for anyone who comes here to get lost, unsure of where to go.
Last time, Lin Yifan stumbled upon Zhou Jiajia by sheer luck; otherwise, he may never have found her even if he searched for a lifetime.
The environment inside the tunnel is still very familiar to him, only now it's a bit more desolate.
