pandas: find the rows where a given column contains certain substring

I have the following code, trying to find the rows in my_df where the values in column_A contain the substring 'abc'.

my_df['abc' in my_df.column_A]

but I got the following error:

KeyError                                  Traceback (most recent call last)
<ipython-input-37-9aaddc5e75d8> in <module>()
      7 
      8 
----> 9  my_df['abc' in my_df.column_A]

/usr/local/lib/python3.4/dist-packages/pandas/core/frame.py in __getitem__(self, key)
   2057             return self._getitem_multilevel(key)
   2058         else:
-> 2059             return self._getitem_column(key)
   2060 
   2061     def _getitem_column(self, key):

/usr/local/lib/python3.4/dist-packages/pandas/core/frame.py in _getitem_column(self, key)
   2064         # get column
   2065         if self.columns.is_unique:
-> 2066             return self._get_item_cache(key)
   2067 
   2068         # duplicate columns & possible reduce dimensionality

/usr/local/lib/python3.4/dist-packages/pandas/core/generic.py in _get_item_cache(self, item)
   1384         res = cache.get(item)
   1385         if res is None:
-> 1386             values = self._data.get(item)
   1387             res = self._box_item_values(item, values)
   1388             cache[item] = res

/usr/local/lib/python3.4/dist-packages/pandas/core/internals.py in get(self, item, fastpath)
   3539 
   3540             if not isnull(item):
-> 3541                 loc = self.items.get_loc(item)
   3542             else:
   3543                 indexer = np.arange(len(self.items))[isnull(self.items)]

/usr/local/lib/python3.4/dist-packages/pandas/indexes/base.py in get_loc(self, key, method, tolerance)
   2134                 return self._engine.get_loc(key)
   2135             except KeyError:
-> 2136                 return self._engine.get_loc(self._maybe_cast_indexer(key))
   2137 
   2138         indexer = self.get_indexer([key], method=method, tolerance=tolerance)

pandas/index.pyx in pandas.index.IndexEngine.get_loc (pandas/index.c:4164)()

pandas/index.pyx in pandas.index.IndexEngine.get_loc (pandas/index.c:4028)()

pandas/src/hashtable_class_helper.pxi in pandas.hashtable.PyObjectHashTable.get_item (pandas/hashtable.c:13166)()

pandas/src/hashtable_class_helper.pxi in pandas.hashtable.PyObjectHashTable.get_item (pandas/hashtable.c:13120)()

KeyError: False

Any idea how to fix this? Thanks!