How To Let Tensorflow Use All CPU

My Linux has 2 CPUs (16 cores per CPU). Each core has 2 threads.

CPU usage rate only 50% less if i use tf.Session(tf.ConfigProto())

CPU usage rate only 40% less if i use tf.Session(tf.ConfigProto(device_count={"CPU": 64}))

Cpu usage rate is 30-70% if i use tf.ConfigProto(device_count={"CPU": 32}, inter_op_parallelism_threads=1, intra_op_parallelism_threads=64, )

And in this configuration all cores are working, but the usage rate is only 30-80%

I have tested in Windows Server (1 cpu / 4 cores). Cpu usage rate is more than 90%.

what should I code can let Tensorflow use all cpu?