http://v4r6k4k35jz3htygpawhyu22hoe2zip3kpwdzogc4g2eup37lpz72yyd.onion/retro
Simply type in whatever you want to search and add "before:" to your search query. Include the colon. After the colon would be the year you want. For example, if I want to search "capirinha before:2008", it would fetch me videos about that old meme that were published before the year 2008.