function checkformcn(theForm)
{
  if (theForm.input.value == "")
  {
    alert("Please input keywords!");
    theForm.input.focus();
    return (false);
  }
}

<!--
function MM_jumpMenu(targ,selObj,restore){ //v3.0
  eval(targ+".location='"+selObj.options[selObj.selectedIndex].value+"'");
  if (restore) selObj.selectedIndex=0;
}
//-->