Most likely the same problem as in the other thread you are using for this question.
Install Chinese-Windows on the Kindle or get the document re-coded into something non-Microsoft.
Specifically, you want a program that reads the right-most column values and replaces (writes) the values in the center column of this table:
http://www.fileformat.info/info/charset/GB2312/list.htm
And then you stand a chance of reading the document as something other than ? ? ? ? ?
If you write the tool in Lua, and it isn't already in Liberartor (or KOReader), then share it with the KOReader project.
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Oh, and the *.chm files are Microsoft proprietary, compiled HTML (such as their 'help' files).
Again, you'll have to find a Microsoft tool that can re-code those for you.
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You could also use KUBRICK to install an early(ier) version of the K4 firmware, and then update using Amazon packages to a newer version, one that still supports your text documents.