How to filter string with condition using python

Looks like you are using "||" as a delimiter between parts of your string, so split your string by that delimiter:

parts = s.split("||")

Then you say "CEO" is a keyword for filtering out a part, so get every part that doesn't have "CEO" in it:

filtered = [part for part in parts if "CEO" not in part]

Finally, put it back together:

output = "||".join(filtered)

Now you get

>>> print output
Jacky Chan ||Managing Director and General Partner, B Robotics || San Francisco Bay Area

I assume the output you posted was incorrectly spaced. If not, well, there's something else to be done here. You'll have to clarify for me.

There's nothing wrong with the other answers, but for the sake of completeness, here's how you could do it with regular expressions. Assumes that | is only used for delimiting.

import re
s ='Jacky Chan || He is a CEO || Managing Director and General Partner, B Robotics || San Francisco Bay Area'
print(re.sub(r'\|\|[^|]*CEO[^|]*\|\|', '||', s))

You can learn all about regular expressions, including the Python-specific bits, in the documentation.

s ='Jacky Chan || He is a CEO ||Managing Director and General Partner, B Robotics || San Francisco Bay Area'
y = "||".join([a for a in s.split("||") if not 'CEO' in a])
print(y)

You can look for CEO and strip away everything between the || separators that contains it, e.g.:

s ='Jacky Chan || He is a CEO ||Managing Director and General Partner, B Robotics || ' \
   'San Francisco Bay Area'

index = s.find("CEO")  # or any other string
if index != -1:  # string found
    replaced = s[:s.rfind("||", 0, index)] + s[s.find("||", index):]
    print(replaced)

# Jacky Chan ||Managing Director and General Partner, B Robotics || San Francisco Bay Area

You could split the string on the || and then rejoin it excluding that segment. So:

s ='Jacky Chan || He is a CEO ||Managing Director and General Partner, B Robotics || San Francisco Bay Area'

s = s.split('||')

s = '||'.join(x for x in s if 'CEO' not in x)

And put it all together for a comprehension:

'||'.join(x for x in s.split('||') if 'CEO' not in x)

Here's also a regex version:

re.sub(r'\|\|[A-z\s]*[CEO]+[A-z\s]*\|\|', "||", s)