int JumpSearchWithCategory(Node *head, string keywork)
{
    int n = length(head);
    int step = sqrt(n);
    int prev = 0;
    int m = min(step,n)-1;

    Node *nMin = getNodeAt(head, min(step,n)-1);
    Node *nPrev = getNodeAt(head, prev);

    while(nMin->book.theloai < keywork){
        prev = step;
        step += sqrt(n);
        if(prev >= n)
            return -1;
    }

    while (nPrev->book.theloai < keywork)
    {
        prev++;

        if(prev == min(step, n))
            return -1;
    }

    if(nPrev->book.theloai == keywork)
        return prev;

    return -1;
}

With this code, I can only find the first guy in the list. Before searching, I sorted the list in order but only found the first guy.

I tried many different ways but it didn’t work, so I came here to ask for help