Read 14.1 entirely.
If the KMT has not collapsed by the end of the game (Fall 1941) the Chinese player wins a Partial Victory. If only the CCP has collapsed, then both sides can claim a Partial Victory, with bragging rights going to the player with Control of more Areas. (In this situation Jiang Jieshi will rule over a reduced but compliant “Free China”, while Japan will incorporate what it has seized into its network of puppet regimes in the “Greater East Asia Co-Prosperity Sphere.”)
You can download the integrated rulebook and charts for the final edition of the game, which incorporates all the errata and rules for the expansion kit (which I hope you will try).
It's all free and it's all there.