You can check if a string contains another sub-string using the in
operator - see this answer for further examples of this.
# put the words you want to match into a list
matching_words = ["apple", "pear", "car", "house"]
# get some text from the user
user_string = input("Please enter some text: ")
# loop over each word in matching_words and check if it is a substring of user_string
for word in matching_words:
if word in user_string:
print("{} is in the user string".format(word))
Running this gives
>>> Please enter some text: I'm in my house eating an apple
apple is in the user string
house is in the user string