Plugin[Multi-domain] : new domain with www or without www issue

Hi Support,

My default domain is http://www.she.com, I tried to create new domain with 'shemom.com' then I create a new site named 'www' with 'shemom.com' like attached image. It's fine if I paste 'www.shemom.com' on browser, but it redirect to http://www.she.com if I paste 'shemom.com(without www.)', how it work both of www and without www?

PS : I just changed my local host ip to do all of the testing.

Thanks.