✔ 最佳答案
The hyperlink provided by 001 is only its "cool" help-desk for basic inquiry which will not help searching mails.
You must check carefully whether your e-mails were accidentally put into some sub-folders you created on your a/c.
First of all, please check the "Trash" and see if they were here. If so, simply move them back to Inbox and the problem is solved.
Else, you need large-scaled searching on your account. If you still remember the name of the e-mail ( title ) or the name of the sender, you can input the information in "Mail Search" item on the bottom of the page, and Yahoo mail will try to search the relevant mails for you.
If you could not search successfully, you need to open page by page to check the names of all e-mails and try to find the one you want. Of course, the date of receiving e-mails would also be a signal for you to locate the approx. page number faster.
If the e-mails were not identified yet, I believe they have been deleted and the server would not have any more record. I mean, they have been lost and there is no chance to reload or to recover them in Yahoo Mails. Do not forget its mailing service is free-of-charge and so, we cannot expect too much provided by their servers.
Last but not the least, recall your memory to see if you have another e-mail copy in other e-mail address. If so, you can still find the materials.
Hope I can help you.
參考: Mathematics Teacher Mr. Ip