function Search_Name() {
  let input, filter, table, i;
  input = document.getElementById("Name");
  filter = input.value.toUpperCase();
  table = document.getElementById("Entries");
  td = table.getElementsByTagName("td");
    
  for(i = 0; i < IDInc; i++) {
    txtValue = td[i].innerText;
                
    if(txtValue.toUpperCase().indexOf(filter) > -1) 
      td[i].style.display = "";
    else 
      td[i].style.display = "none";
  }
}

I tried this javascript code to search for names case insensitive only to get buggy/unstable results.

How to fix it?

And thanks.

(Note: IDInc is the length of the Names array; ID is just the the position of names in array and not necessary for the search function)