Outlook’s search folders help find emails

Can’t find that email?
Don’t give up – read on
Outlook’s search folders are useful for finding emails. They keep your unread mail and your emails from selected addresses in separate folders for quick and easy consultation, no matter where you might have filed them. The emails are not moved there, just displayed.
Unread emails
Right-click on the Search folders folder and left-click on the New Search Folder button that pops up.
The New Search Folder dialog box pops up. Select the option you want, in this case Unread Mail, as shown below:

That may be enough for you, but I prefer my unread mail to be even more prominent so I added the folder to my Favourites.
Add to Favourites
Display the folder amongst your Favourites by right-clicking on it and choosing the Add to Favorites option from the drop-down menu shown below:

The Unread Mail folder is added to the Favourites folder at the top left of the screen in the Folder Pane, as shown below.

You can go even further and make Outlook open in the Unread Items folder.
Open in the Unread Items folder
To make sure you do not forget any of your unread emails, you can make Outlook open in the in the Unread Items folder instead of your Inbox.
Go to File > Options > Advanced. In the right-hand pane of the Outlook Options pop-up, the second group from the top is called Outlook start and exit. Click the Browse button and select the Unread Mail folder, as shown below.

Emails from certain people or organisations
Right-click on the Search folders folder at the bottom of your email folders and left-click on the New Search Folder button that appears.
The New Search Folder dialog box pops up. Select the option you want, as shown below (drag a corner diagonally to enlarge the image):

If you select one of the Mail from People and Lists options, click the Choose button to tell Outlook the address you want. The Select Names: Contacts dialog box pops up. If you don’t have the email address amongst your contacts, you can type or paste it into the From or Sent To textbox, as shown below:

Now you will be able to see all the mail to and/or from that address under the name highlighted in the Search Folder. You can right-click on the name to change it or customise its contents, as shown in 1.c.