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If you don't want to take time to organize your email, you can stick to sorting (by clicking column headings such as From, Subject, and Date Received) and searching (by typing text in the Search text box in the upper-right corner of the Mail window).
If you're willing to take time to organize your email, use Smart Mailboxes and rules. Since Smart Mailboxes create links to messages physically stored in the Inbox folder, you can look for messages in both the Smart Mailbox and the Inbox folder. If you prefer reducing clutter, use rules to move messages physically into specific folders.