- var_dump: documentation ( source)
<?php
$html = <<<EOF
<table>
<tr>
<td>something</td>
<td>...</td>
<td>...</td>
</tr>
<tr>
<td></td>
<td>...</td>
<td>...</td>
</tr>
<tr>
<td></td>
<td>...</td>
<td>...</td>
</tr>
<tr>
<td>anything</td>
<td>...</td>
<td>...</td>
</tr>
<tr>
<td></td>
<td>also find</td>
<td>...</td>
</tr>
<tr>
<td></td>
<td>this too</td>
<td>...</td>
</tr>
<tr>
<td>other</td>
<td>...</td>
<td>...</td>
</tr>
<tr>
<td></td>
<td>...</td>
<td>...</td>
</tr>
</table>
EOF;
$doc = new DOMDocument();
$doc->loadHTML($html);
$xpath = new DomXpath($doc);
$res = $xpath->query('//td[contains(text(), "anything")]/../following-sibling::tr');
foreach($res as $tr){
var_dump($doc->saveXML($tr));
}