Search in Outlook Web App

You can also use Advanced Query Search, or AQS, to refine your searches. To use AQS, type a keyword followed by a colon, and then what to search for in the search box. For example, to find any message with a subject that contains “tomorrow”, enter subject:tomorrow in the search box.

AQS keyword	Description
From	Searches the From field.
To	Searches the To field.
Cc	Searches the Cc field.
Bcc	Searches the Bcc field.
Participants	Searches the To, Cc, and Bcc fields.
Subject	Searches the subject.
Body or Content	Searches the message body.
Sent	Searches the date sent. You can search for a specific date or a range of dates separated by two dots (..). You can also search for relative dates: Today, tomorrow, yesterday, this week, next month, last week, past month. You can search for the day of the week or month of the year.
Received	Searches for the date received. You can use the same search terms as for Sent.
Category	Searches the Category field.
Attachment	Searches for the specified attachment by title. For example, attachment:letter.doc will find any message with an attachment named letter.doc.
Has	Use has:flag to find items that are flagged. Use has:attachment to find items that have one or more attachments.

When you use AQS, you can search on multiple search terms. When you enter multiple search terms, you can search on any, all, or an exact phrase.

• Subject: product plan will find any message with “product” or “plan” in the subject.
• Subject: (product plan) will find any message with both “product” and “plan” in the subject.
• Subject: “product plan” will find any message with the phrase “product plan” in the subject.

http://office.microsoft.com/en-ca/office-online-help/search-in-outlook-web-app-HA102929994.aspx