why speech_recognition does not work after exe-pack by pyinstaller?

Question

I am having problem with pyinstaller. when I run following code with anaconda, operation is fine. (automatically collect audio file and write text). but if I made exe with pyinstaller (one file mode). exe file does not work... I am wondering if there is way to make this work.

windows 10 anaconda python 3.4

import pydub, os
import speech_recognition as sr


#read wav file and Write out text to document.txt.
def auido2text():
    docuFile = open('document2.txt', 'w',encoding="utf-8_sig")
    
    for Filename in os.listdir('.'):
        if not Filename.endswith('.wav'):
            continue  #skip non-wav files
    
        r = sr.Recognizer() 
        with sr.AudioFile(Filename) as source:
            audio = r.record(source)
         
        text = r.recognize_google(audio, language='es-ES')
        
        docuFile.write(text)
        docuFile.write('\n\n')
    docuFile.close()

auido2text()