Before you hunt, you need to understand the resolution. That '70s Show was shot on 35mm film, which theoretically supports 4K. However, the CGI and special effects (like the iconic circle shots) were rendered for Standard Definition (480i) or early HD.
Here is why 720p is the perfect balance:
If you find a 720p x265 (HEVC) encode, even better. You can fit the entire series into 20GB without visual loss. Index Of That 39-70s Show 720p
Downloading That '70s Show from an unindexed server is copyright infringement in most jurisdictions. However, the "Index Of" method resides in a legal gray area because the files are technically publicly accessible without a password. Courts have historically ruled that exploiting directory indexing is still infringement if you download copyrighted material.
Safe Alternative: Use YouTube's free-with-ads versions (usually 480p only) or purchase the complete series on Vudu/Apple TV, which streams in true 720p/1080p. Before you hunt, you need to understand the resolution
If you truly want the "39-70s" variant, try:
"index of" "parent directory" "that 70s" -xxx -xxx
Often, file names get corrupted. A file named That.39.70s.Show.S03E09.720p.mkv might be the only trace of that naming convention. If you find a 720p x265 (HEVC) encode, even better
intitle:"index of" "that 70s show" (720p|1080p) -htm -html -php -asp -jsp
Breaking it down: