you can t you only get enough stars to buy everything in the shop and that's it.
by playing the game instead of looking on the internet for a cheap way out.
nope
Collect stars.
You can only do the missions.
After you beat a mission in Dragon Ball Collection when you go back to that mission it will show a list of things you have to do. Once you complete one you get a star there will be 3 for you to complete.
do bonus objectives in a battle. (Only avalible after you beat it the first time.) click on a battle and click "mission" and do what it tells u to do in the battle and earn stars.
Buy it with stars,which you obtain by the db ball.
after you complete a battle, go back to it and you will see "missions"there it will tell you what you need to do.
you need to obtain 20 stars in dragon battle collection, and buy the secret Battle 47 (What-If Stories) - beat this battle to unlock ssj3 vegeta (it is a separate character from vegeta as it is not canon)
after you beat a mission you go back to one you beat and hit mission and it will show you how to get 3 stars on that mission there are three stars per mission.
in dragon battles mode, ther is a place called star shop, to get stars u hav to check the mission for the level u r playing....in order to c the mission u hav to beat the level first
All you have to do is go to a mission you completed,look for "mission" at the bottom,click on "mission",look at the missions,and if it shows something you can do,play the battle and get the stars.