Right-click the downloaded file and click the opening method of HowNet Research. On the right, you can create a new topic or sub-topic as needed, select the topic to save (example in the figure: information user research), and then click Import Only. Then you can see the documents you need in HowNet research. Click any document, click the blue arrow on the right to see some related information of the document, and double-click the topic to see the text of the document.