How it can be possible a brand name i.e BestWay is a registered TM name for multiple companies across the globe? Please explain.
It happens all of the time.
Trademarks are words, symbols, etc. by which consumers in a relevant market recognize products and are able to distinguish among competitive goods.
If I sell a popular brand of clothing called "FOO" in my area, such that consumers recognize "FOO" as indicating the quality and type of shoes sold by me; and if nobody else in my area is selling "FOO" brand shoes, then it functions as a mark for shoes in my area. There might be someone in India selling "FOO" brand cigarettes, but that's not going to cause any consumer confusion among shoe purchasers where I am, nor is it going to cause any consumer confusion among smokers in India.
Not all trademarks are of equal strength, scope or fame. For example, if I start selling a brand of shoes called "COCA-COLA", then I'm going to have a problem with the fact that it is such a well known, famous and distinctive mark, that consumers might believe my shoes originate with the maker of that brand of beverage.
This can even happen on a smaller scale within a country. For example, in the United States, the mark "USC" is used by the University of Southern California, and by the University of South Carolina, on two opposite ends of the country. Each of them has a US registered trademark, but the exclusive rights in the trademarks are geographically restricted to respective uses east of the Mississippi River, and west of the Mississippi River.