使用Series.isin()即可，例：
检查['a', 'b', 'c', 'd', 'e', 'f']的每一个元素是否在['a', 'b', 'bc', 'd', 'e']中

import pandas as pd

series = pd.Series(['a', 'b', 'c', 'd', 'e', 'f'])
union_series = series[series.isin(['a', 'b', 'bc', 'd', 'e'])] # 取交集
print(union_series)