Thank you for your comment,marcus.
Like you said,all subtools arent deleted. I pushed “Up arrow” button and I find there are all subtools still other than body07 subtool. I pushed Up arrow button to restore the subtool list, but couldnt find the Body subtool, which is the object I tried to partially hide. And I turned off and turned on the eye icon of the subtools, Eye and Hair, and I could recover the body07 subtool, which wasnt listed in Subtool list though. Then Ctrl+Shift+Clicking on the Body object on the canvas, then finally I could restore the body07 subtool on Subtool list, but the body07 subtool was moved upward a little.
I attatched the pictures that shows the situation.
You may notice The Body subtool is slightly moved upward after this process because the inner mouth part, which is a subtool named as bottom mouth, is visible.Do you know why?

Pic No3 shows the original position of subtool body07.
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