I don’t want dead after 1 boss hit like now 
This is very vague. If you are getting killed by 1 hit then something is wrong with the way the build is made
Getting one shot = resists are non-existent.
Many builds are OP in different situations. All builds which are OP are balanced in both offence and defense. The only way to get something OP is to understand game mechanics.
Why can’t a person just replicate a build without understanding mechanics? Simply put, ALL OP builds are item dependent (admittedly some are moreso than others). If you don’t understand mechanics, you won’t be able to improvise and use cheaper item alternatives as you’re leveling the toon, thereby rendering it ‘useless’
Furthermore, different characters demand different playstyles. For example, if running/gunning is something you enjoy, giving you a sword/shield build wouldn’t make sense.
The fault of the toon would therefore lie with the pilot, and not its inadequacies.
As Username said, it could be your resists, it could be you HP pool, it could be your DA. There are too many unknowns for us to help you.
Perhaps link us your build? In the mean time, I suggest reading - http://www.grimdawn.com/forums/showthread.php?t=69750