First, open the document and double-click the mathematical formula with the display problem. At this point, the formula editor will start automatically. Click Style-Definition in the Formula Editor interface, and click Advanced in the pop-up Define Style dialog box.

At this time, you can see the font settings in the formula editor, paying special attention to the settings of variables, lowercase Greek letters and symbols. If your system does not support this font, the formula editor cannot display the mathematical formula correctly. The easiest way is to click the factory settings on the right and restore to the default settings. Of course, you can also select the font you like and install in your system in the corresponding drop-down list box, so that it can be displayed correctly after setting and entering the formula. It is suggested to use "Times New Roman" font for variables and "Symbol" font for lowercase Greek letters and symbols. General windows systems install these two fonts by default.

What you see in Word is garbled, but what you see after entering the formula editor is the correctly displayed formula, and it becomes garbled after exiting the formula editor. In fact, this is because the formula is automatically displayed in the font supported by your system in the formula editor, but it is not updated in the word document. At this time, you only need to click "File-Update Document ..." or press the shortcut key "Ctrl+S" in the formula editor to update the formula font into the document. After exiting, you can see that the formula has been displayed normally.