Finding online platforms that offer detailed explanations for previous years' Anthropology optional questions can be a challenging task, but with the right approach, it is possible to find reliable resources. Here are some steps you can follow to find such platforms:

1. Search on EduRev: EduRev is a widely recognized educational platform that provides a vast range of study materials, including previous years' question papers and detailed explanations. You can start your search by visiting the EduRev website and looking for the Anthropology optional section.

2. Browse through UPSC Forums: There are several online forums dedicated to UPSC preparation where aspirants discuss and share resources. Explore these forums and look for threads related to Anthropology optional questions. Often, users provide detailed explanations and analysis of previous years' questions. Keep an eye out for popular forums like Insights on India, ForumIAS, or Quora.

3. Join Anthropology Optional Telegram/WhatsApp groups: Telegram and WhatsApp groups have become popular platforms for UPSC aspirants to connect and share resources. Joining groups specifically focused on Anthropology optional can help you find study materials, including detailed explanations for previous years' questions. Look for groups with a large number of active members and positive reviews.

4. YouTube Channels: Many UPSC preparation YouTube channels upload videos with explanations for previous years' questions. Search for channels that specialize in Anthropology optional and explore their playlists. Some popular channels like Unacademy, Study IQ, or Drishti IAS often provide detailed explanations for UPSC optional subjects.

5. Online Study Materials: Some websites offer comprehensive study materials for UPSC optional subjects, including Anthropology. Look for websites that provide detailed notes, question banks, and explanations for previous years' questions. While EduRev can be a good starting point, make sure to explore other reliable platforms as well.

Remember to cross-check the information and verify the credibility of the platforms you come across. Always refer to trusted sources and materials recommended by experienced UPSC mentors or successful candidates. With a diligent search and careful evaluation, you can find online platforms that offer detailed explanations for previous years' Anthropology optional questions.