Bic Chrome Platinum work very well for me in the 34C.
You really have to look to maintain the optimum angle to make it cut efficiently.
This.
A different, more aggressive blade might help, but the key with the 34C is understanding the optimal angle (I also found this to be important with the Karve)
I’ve had a bunch of frustrating shaves with the 34C before I stumbled upon the perfect angle by accident (more head leaning than lip leaning), and since then I get great shaves with it, yet still super safe.