I want to make one HTML page of my site to be not indexed by search engines. How can I do that? And I also wonder how to make a certain text on my site to be not indexed by search engines? What tags should I use?
Add this line of code to your HTML: <META NAME='robots' CONTENT='noindex, nofollow'> Code (markup): This will stop most robots from indexing the page AND from following links on the page. If you want no indexing but following of links, then do this: <META NAME='robots' CONTENT='noindex, follow'> Code (markup): As far as not indexing certain parts of the page, I have no easy answer, as there are multiple ways of doing it. Simplest way is to refrain from putting non-indexable content on an indexable page.
You can make a separate robots file, but for one page as the OP wanted, a robots page is overkill. Much simpler just to use a one-line meta tag.
Actually there's not an efficient method to blog the indexing as long as your website has been crawled by google.
You take the page down and replace it with a page with the correct tags at a different location. The old non-existent page will drop off google in a few months and the new one won't be indexed. You can also ask google to take down the non-existent page earlier.