MacMail help

Hi, so i setup MacMail to access my gmail account via iMap (as i wanted all mails to be stored on the server).

Everything works alright but when selecting 'gmail' from my inbox section in MacMail it doesn't have all of the emails that are actually in my gmail inbox. I have to select on the left hand side the bottom menu here it nests from gmail and select 'all mail' before i see the others that are in my inbox.
how can i make gmail work properly with MacMail?

 

yeah sorry, im a mac newby