Доступ к данным в фреймворке Pandas

IIUC необходимо:

df = pd.DataFrame({'col1':['This is a paragraph','This is a second paragraph'],
                   'col2':[['if-statement', 'for-loop'],['for-loop','java']]})

df = df[df['col2'].apply(lambda x: 'java' in x)]
#alternative solution
#df = df[['java' in x for x in df['col2']]]

Или сравните sets:

df = df[df['col2'].apply(set) >= set(['java'])]

print (df)
                         col1              col2
1  This is a second paragraph  [for-loop, java]

Как насчет использования map.

>>> df['col2'].map(str)[1]
"['for-loop', 'java']"