These days, you can do most work online, and I was able to do the Snowman Trek I on the Google Earth as well. When I wanted to look at the locations and routes of this trek, known as one of the toughest in the world, the first and most authentic source was the Tourism Council website. However, the website did not give most of the locations correctly. Many of the places after Thanza are clustered around this place. Then I came across a beautiful and very detailed trip report from a trekker who did this trek in the fall of 2019. I read his report and looked at his maps and traced the trail on Google Earth. In most places, the trail is clearly visible, even in the snowy sections. However, in some places there are some clouds during the image capture time by the satellite and in some places covered by dense forest and sometimes along riverbanks.
According to the Tourism Council website, this stretch of the Snowman Trek takes 25 days and passes through many high altitude lakes and passes. Two of the passes, namely Ganglakarchung La between Laya and Lunana and Rinchen Zoe La between Lunana and Sephu, are the most difficult on this trek. They are higher than 5000m and remain covered under snow most of the year.
This is a map showing the route marked on, but may not correspond exactly to the trek on the ground but through such interactive maps we can have a virtual tour of the trek.