Does it have a submission ID ?

If you highlight the file in the EFCenter, and hit F12 the Efile Reports window should open, choose Acknowledgements and see what it says.

Oh and you cant just use Receive Acks (if you already pulled the ack once it will say none exist), you want to highlight the client file then choose Update Acks for Selected Returns

have 10 clients which were filed electronic, and does not appears to be filed 

electronic filing, I have filed and submitted 10 clients which does not shows as received