Write a function `find_max_difference` that takes a binary string as input and returns the maximum difference between the number of `0`s and `1`s in any substring of the given string. If no such substring exists, return `0`.
#### Example Usage
```python [main.nopy]
find_max_difference("11000010001") # Output: 6
find_max_difference("10111") # Output: 1
find_max_difference("1111") # Output: 0
```
#### Constraints
- The input string will only contain characters `0` and `1`.
- The length of the string will be between `1` and `10^5`.