Not for years had she felt more content. This sentence is taken from Collins. The Chinese Translation of the Collins translates this sentence into something like 'She hadn't felt content for many years.' or like 'It was not a long time since she began to feel fairly content.'
But I would think this sentence means 'She hadn't felt more content for years than she did now.' or rather, 'she felt more content now (=then) than she had in the last few years.'
I wonder if I am right. Could I ask native speakers to help me please? Thank you in advance.
You are correct. The other translations are misleading and even inaccurate, as you recognize.