Reading an attachment in an incoming email needs that you through the UI of the email application. In outlook, go to the email, click the attachment then click open and not save. If the attachment is in PDF, you can attach the window at the place where PDF opens. Add this filter in the outlook activity: “[Attachment]=’*.pdf’”
To filter the mails with a specific word inside them, you need to search for that word in the attachments one by one. If this is a long and slow process, save the attachments and read the files to find the word. After this, you can delete them.