<h3>Ignore h3</h3>
  <p>Ignore p</p>
  <h2>Locator</h2>
  <h3>Header 1</h3>
  <p>Paragraph 1.1</p>
  <h3>Header 2</h3>
  <p>Paragraph 2.1</p>
  <p>Paragraph 2.2.</p>
  <p>Paragraph 2.3.</p>
  <h4>test header 4</h4>

//h2[contains(text(),'Locator')]/following-sibling::*

//h2[contains(text(),'Locator')]/preceding-sibling::*[1]/following-sibling::*

//*[preceding-sibling::h2[.="Locator"]] | //h2[.="Locator"]