How to increase the accuracy of the vosk module in Python?

How to maximize vosk module accuracy?
I use the «large» model
Thanks

codes:
model = Model("vosk-model-fa-0.5")
wf = wave.open("audio.wav", "rb")

rec = KaldiRecognizer(model, wf.getframerate())

while True:
data = wf.readframes(8000)
if len(data) == 0:
break
if rec.AcceptWaveform(data):
a=rec.Result()
else:
a=rec.PartialResult()

a=rec.Result()