import re
mylist = ["dog", "cat named bob", "wildcat", "thundercat", "cow also named bob", "hooo"]
r = re.compile('named')
# You might gfo through the list, check if there is match 
# by running a re.search, and there is, extract it
newlist = [r.search(x).group() for x in mylist if r.search(x)]
print(newlist)
# Or, use map to get the matches first, and then 
# check if the object is not None and then retrieve the value
newlist = [x.group() for x in map(r.search, mylist) if x]
print(newlist)