from typing import List


def helper_get_subsequences(s: str) -> List[str]:
    """Helper function to get subsequences from a string."""
    sequence = s.split()
    if len(sequence) <= 2:
        return []
    answer = []
    for left in range(len(sequence) + 1):
        for right in range(left + 1, len(sequence) + 1):
            if left == 0 and right == len(sequence):
                continue
            answer.append(" ".join(sequence[left:right]))
    return answer