You can try this method:-
1. Go to themeforest.net and search for themes you would require
2. Download Tor browser (It is an free open source browser which helps maintain online privacy)
3. Copy & paste the title of the theme you have selected from themeforest.net into Tor Browser search field and add "nulled" keyword at the end.
4. Many websites will appear which would generally get blocked by google or other search engines.
5. Just go back and forth to different websites (Usually 1st tab is enough) and you will get that theme 90% of the time.
P.S. - Make sure to check the Theme changelog at the official website to ensure you're getting the most recent version of the theme.
