Clock [Q] in KK.4.4.2 Native Exchnage Email App email-search does not work ?

Greetings folks,

I want to use to Native Email App which came with N5, KK (4.4.2). After the update to 4.4.2, I was able to configure my Official Email account using SSL certificates. But I am still not able to -

1. Search the emails
2. Auto Sync my sub folders. I have to enter them and swipe it down to sync it. No auto email notification like inbox.

I am using TouchDown the free version. It is expensive to buy a license, plus it is not well integrated with ROM.

I rooted and installed KangKat and then Carbon, thinking probably it may work in any of them. It did not.
What do you recommend. I have checked with other fellows in the team, they say the Native App sucks, and it does not have search capability, some of them shifted Galaxy-4. I could not find any touchwiz ROM, or for what matter any any HTC Rom. I am sure their email app are better than Native Exchange Email App by Google.

Please recommend I need to -
1. an Email Client which is able to do two authentication. I mean in which i shall be able to import my certificate before i connect to the exchange/mail server.
2. be able to search my email
3. Sync my Calendar
4. Sync my sub folder.

Another good to have feature, probably i will spend time later figure out how to change the ROM, so that when i install SSL certificates for phone, it does not by default enforce security and i have to put a lock-pin (such a time waster).

Thank you fellows.

Vivek Sharma
Nexus 5 | Carbon ROM