Enable "Search Page Selection in Background" to do a search, but check the results later.
Enable search suggestions to get suggestions from the search engine as you type.
Find similar images with reverse image search.
Search for specific words on the open web page in Vivaldi on Android with Find in Page.
Add a new custom Search Engine to Vivaldi from the site search field's context menu.
Add Vivaldi's search widget to your mobile device's home screen to start a search with just one tap.
Highlight text on a web page, right-click on the selection and select "Search..." to get results in an instant.