Python: Check if string and its substring are existing in the same list : <p>I've extracted keywords based on 1-gram, 2-gram, 3-gram within a tokenized sentence</p>

<pre><code>list_of_keywords = []
for i in range(0, len(stemmed_words)):
    temp = []
    for j in range(0, len(stemmed_words[i])):
        temp.append([' '.join(x) for x in list(everygrams(stemmed_words[i][j], 1, 3)) if ' '.join(x) in set(New_vocabulary_list)])
    list_of_keywords.append(temp)
</code></pre>

<p>I've obtained keywords list as </p>

<pre><code>['blood', 'pressure', 'high blood', 'blood pressure', 'high blood pressure']
['sleep', 'anxiety', 'lack of sleep']
</code></pre>

<p>How can I simply the results by removing all substring within the list and remain:</p>

<pre><code>['high blood pressure']
['anxiety', 'lack of sleep']
</code></pre>
