seeing mails on macbook I live in Shanghai for last 5 years operating a microsoftonline.com email account on my macbook (version 10.10.2) and iphone6. 

Until few months ago, it always went well. Lately,  many a times I can’t open/see mails on my macbook while the same mails are visible on my mobile. Some of these mails are the ones that I have opened on my mobile first but some of the mails still do not open on my macbook even if I dont open them on my mobile first. In fact, few mails are still clearly visible in my macbook even if I’ve opened them on my mobile earlier. 

This problem never happened before. The gmail has been banned in China so I can’t check some mails sent on my gmail accounts unless I connect to VPN. For microsoft outlook, there is no such problem but still I can’t open mails on macbook. 

Also when I’m in office I use same wifi connection both on iphone and macbook. Still some mails are not visible in macbook but all the mails are visible in iphone. I dont understand where is the problem ?

Kindly help !!!
I used to have tons of sync issues when attempting to use certain Exchange accounts with Mail.app and issues are still being reported with Yosemite: 

see this discussion - https://discussions.apple.com/message/26903397#26903397 

If you have to use a Microsoft account and you're running a mac, you might want to consider changing your mail client. The user above actually has gone back to using Outlook 2011 for compatibility.