<td clospan="2" id="text"> == $0
>input type="tttt" name="YYYY" Value="KKKK" onkeydown="srch_complex(0)"
size="25">
<a hrer="javescript:srch_CCCC(1)"Query</a>
</td>

IWebElement element = driver.FindElement(By.XPath("a[href='javescript:srch_CCCC(1)']"));
element.Clear();
element.SendKeys("UUUU");

IWebElement element = driver.FindElement(By.ID("text"));
element.Clear();
element.SendKeys("UUUU");