I have the following data frame df1

       string             lists
0      i have a dog       ['fox', 'dog', 'cat']
1      there is a cat     ['dog', 'house', 'car']
2      hello everyone     ['hi', 'hello', 'everyone']
3      hi my name is Joe  ['name', 'was', 'Joe']

I'm trying to return a data frame df2 that looks like this

       string             lists                         new_string
0      i have a dog       ['fox', 'dog', 'cat']         i have a
1      there is a cat     ['dog', 'house', 'car']       there is a cat
2      hello everyone     ['hi', 'hello', 'everyone']   
3      hi my name is Joe  ['name', 'was', 'Joe']        hi my is

I've referenced other questions such as https://stackoverflow.com/a/40493603/5879909, but I'm having trouble searching through a list in a column as opposed to a preset list.

Considering that the dataframe is df, and that OP's goal is to create a new column named new_string whose values are strings equal to the one's in the string column without a string in the lists column, for that specific row, the following will do the work

df['new_string'] = df['string'].apply(lambda x: ' '.join([word for word in x.split() if word not in df['lists'][df['string'] == x].values[0]]))[Out]:string                  lists      new_string
0       i have a dog        [fox, dog, cat]        i have a
1     there is a cat      [dog, house, car]  there is a cat
2     hello everyone  [hi, hello, everyone]                
3  hi my name is Joe       [name, was, Joe]        hi my is