# import necessary libraries
import pandas as pd

# define your series
series = pd.Series(['apple', 'banana', 'cherry', \
                    'plum', 'orange'])

# using Python count method
words = [word for word in series 
          if word.count('a') + word.count('e') + \
             word.count('i') + word.count('o') + \
             word.count('u') >= 2]

# print filtered words
print(words)