Different bearers created for different qci can be differentiated using TFT. Every bearer have DL and UL TFT. UL TFT is enforced by ue. TFT can have port range or destination IP etc. So if ue is having sip data to send in UL and it is expected to go through qci 5 bearer then ue will match TFT . If TFT is matching with qci 5 bearer then ue will send with qci 5 bearer otherwise he will send with default bearer.