How about this
"No hard proof evidence. That's why he chose a successor, which is near to continue his investigation and find evidence."
Are you sure that was written by a native speaker? Not only does "hard proof evidence" sound wrong, "which is near to continue..." makes no sense.
Also, "No hard proof evidence" isn't a complete sentence".
This might make sense if it said "He has found no hard evidence. That's why he has chosen a successor, who is here to continue the investigation and find some evidence."