Find words or phrases on a web page
If you're looking for a particular word or phrase on a web page, you can find it by typing the word or phrase in the URL/search bar at the top of the screen. (As soon as you tap on the top bar the page you were on will be replaced by a screen filled with your Favourites, but don't worry - you're still on the web page. It'll return as soon as you tap off the top bar or run the in-page search.) You'll see a list of web search results - and search results from the App Store, Wikipedia and so on if applicable, but you need to look at the bottom of that list for a section labelled "On This Page", with the number of matches.
Tap it, and you'll see that the results are highlighted on that particular web page in yellow. Tap the arrows at the bottom of the screen to go to the next instance.