This bird really doesn't look like a (pure) dusky thrush at all - even juveniles of those would have a broad white supercilium, a black-streaked back, black spots on the flanks and an entirely rufous upperwing.
I think it might be a juvenile red- or black-throated thrush instead, but hybrids between those (and other similar species like Naumann's) are notoriously common, and identification from pictures of the back alone might not be 100% certainly possible... And I'm not familiar enough with Asian thrushes to be able to exclude other options.
