extract the line by matching the word in text file : I have one text file file which contain text and other is csv file which contain designation i want to extract the line where designatnation is match.

    import nltk
    import re
    import pandas as pd
    
    with open('textfile.txt', encoding='utf16') as f:
        sample = f.read()
         
    file = pd.read_csv('designation.csv')
    df = pd.DataFrame(file)
       
    data = []
    
    for i in range(len(df)):
        des = df.loc[i]['Designations']
        for line in sample.splitlines():
        	print(line)
        	des_regex = r'[a-zA-Z]'+des+r'[a-zA-Z]'
        	regular_expression = re.compile(des_regex, re.IGNORECASE)
        	regex_result = (re.search(regular_expression, line))
        	if regex_result:
        		data.append()


Input text file 

" Sunder Pichai is the CEO of Google. Google is the american company
Google began in January 1996 as a research project by Larry Page and Sergey Brin when they were both PhD students at Stanford University in Stanford, California.[9]

While conventional search engines ranked results by counting how many times the search terms appeared on the page, the two theorized about a better system that analyzed the relationships among websites.[10] They called this new technology PageRank; it determined a website's relevance by the number of pages, and the importance of those pages that linked back to the original site.[11][12]

Page and Brin originally nicknamed their new search engine "BackRub", because the system checked backlinks to estimate the importance of a site.[13][14][15] Eventually, they changed the name to Google; the name of the search engine originated from a misspelling of the word "googol",[16][17] the number 1 followed by 100 zeros, which was picked to signify that the search engine was intended to provide large quantities of information.[18] Originally, Google ran under Stanford University's website, with the domains google.stanford.edu[19] and z.stanford.edu.[20]"

input csv file which contain designation like 

    CEO,
    CTO,
    COO 

I want to output like 

    Sunder Pichai is the CEO of Google
