If you use Gmail in a web browser then you've probably noticed the options for sorting your email or finding a particular email are quite different from email programs. The below article tells you how to find just about anything in Gmail - extremely useful if you're a Gmail fan.
The article lists a large variety of search operators you can use to find anything in your Gmail account. For example, you can search for unread email, emails from certain people, or email containing certain subjects or words. You can find email from people in your Google+ circles, by date, by message ID header, chat messages, and if you use labels or stars in Gmail you can search for those too.
If you'd rather view your Gmail in an email program, directions on how to set up Gmail in an email program can be found here. If you're having problems sending or receiving emails in your email program, check the settings there, you might have something configured incorrectly. Last, you can find many answers to common issues at the Gmail Help Center.
Link to Sorting and Finding Emails in Gmail