Welcome to Flyer Talk mrster

If I understand correctly you have entered an itinerary in the online xONEx around the world booking tool, and you are getting error messages?

What are the error messages? I can guess at some of them from the information you have provided.

When you enter the next destination in the tool it searches on the specific date for direct flights as well as flights via the hubs with a "reasonable" connection time. Very short and long connections are not returned. So you can sometimes find more flights by varying the dates, and by breaking the search down into smaller segments. Eg instead of searching say Delhi to Bangkok, neither of which is a hub, try Delhi to Hong Kong and Hong Kong to Bangkok separately. Repeat for other cities as transit points eg Tokyo, Singapore.

On xONEx fare (unlike some other around the world fares) it is okay to backtrack within a continent. Tokyo and India are in the same continent.

You start in North America and finish in South America. You need to return to the continent you started in.

There are no flights between Asia and South America. The only options are to route through Australia/NZ, or through North America. Going via North America is not an option for you because you began your itinerary in North America (once you return to the continent of origin you cannot travel to another continent), with one exception. There is a flight from Tokyo to Sao Paulo on Japan Airlines. If you can find availability on that flight all the way through then technically you are not travelling via North America.

I hope this helps.