[python] Find common substring between two strings

In case we have a list of words that we need to find all common substrings I check some of the codes above and the best was https://stackoverflow.com/a/42882629/8520109 but it has some bugs for example 'histhome' and 'homehist'. In this case, we should have 'hist' and 'home' as a result. Furthermore, it differs if the order of arguments is changed. So I change the code to find every block of substring and it results a set of common substrings:

main = input().split(" ")    #a string of words separated by space
def longestSubstringFinder(string1, string2):
    '''Find the longest matching word'''
    answer = ""
    len1, len2 = len(string1), len(string2)
    for i in range(len1):
        for j in range(len2):
            lcs_temp=0
            match=''
            while ((i+lcs_temp < len1) and (j+lcs_temp<len2) and string1[i+lcs_temp] == string2[j+lcs_temp]):
                match += string2[j+lcs_temp]
                lcs_temp+=1         
            if (len(match) > len(answer)):
                answer = match              
    return answer

def listCheck(main):
    '''control the input for finding substring in a list of words'''
    string1 = main[0]
    result = []
    for i in range(1, len(main)):
        string2 = main[i]
        res1 = longestSubstringFinder(string1, string2)
        res2 = longestSubstringFinder(string2, string1)
        result.append(res1)
        result.append(res2)
    result.sort()
    return result

first_answer = listCheck(main)

final_answer  = []


for item1 in first_answer:    #to remove some incorrect match
    string1 = item1
    double_check = True
    for item2 in main:
        string2 = item2
        if longestSubstringFinder(string1, string2) != string1:
            double_check = False
    if double_check:
        final_answer.append(string1)

print(set(final_answer))

main = 'ABACDAQ BACDAQA ACDAQAW XYZCDAQ' #>>> {'CDAQ'}
main = 'homehist histhome' #>>> {'hist', 'home'}