Thanks for your quick response!
For my case, applying B1, do I need business invitation letter to apply B1?
-Yes. B1 duration is cery short, so it is not a good choice.
Does the letter from my current employer work fine or I have to get business invitation letter from other company than my current employer?
-Either, but have to have a convincing reason for B1.
I have relative in the U.S, is it easy for me to apply B2 than applying B1 (business)?
-Irrelevant. Either B1 or B2 can not solve your problem unless you marry a US citizen. Otherwise, you may just leave US for one year and get a new 6 year H1 term.
Which one takes better chance to get B visa approval? Do I also need invitation letter from my relative too if I apply B2?
how to write the B1/B2 invitation letter? what reason should be used
