CMRA stands for a Commercial Mail Receiving Agency.
See example:
http://freshdesk.com/about Freshdesk, Inc.
340 S Lemon Ave #7585
Los Angeles, CA, 91789, USA
The #7585 in the address is the dead giveaway they are using a CMRA. A real street address is really easy to get in nearly any other part of the world except the US. Any solution for that?
Getting a street address in the US is easy. Both UPS and USPS offer that service. See here and here.
In terms of replacing #box with something so that it's not obvious it's a P.O. Box, you can use "suite". So using your example:
Freshdesk, Inc.
340 S Lemon Ave, suite 7585
Los Angeles, CA, 91789, USA
I don't think they officially support the use of the word suite, but depending on your needs it may be good enough.
Of course if someone uses Google Maps to find your address, it'll be obvious it's a P.O. Box.
Adding an additional point, If you want to bypass the Google Maps / PO box issue that Zuly mentioned, you can sign up with a shared office space company - mail / packages can be received & forwarded as needed. Here's a example of a company that offers such services worldwide - there are others.
Are you looking for a street address without a suite or apartment number? Those are assigned to a physical piece of property in the US.
If suite numbers are acceptable (which vast numbers of US businesses use) consider the Merchandise Mart in Chicago. The building is so large that it has its own zip code. It has suites numbered in the thousands. So what is wrong with a large suite number?
There are plenty of mail holding and forwarding services that offer boxes with numbers from 1 - 1,000. You can refer to them as box, suite, apt, or whatever.