One of the problems with bush tomato plants is that when they are laden with fruit, the weight of the toms sometimes pulls a branch away from the main stem.
If this happens, all of the toms on that branch will of course stop growing, so it's a good idea to identify any branch that looks vulnerable and support it in some way.
You can see in the pic above that the tomato plants have their laden branches supported with string. A stake is also very useful but do be careful with short stakes and make their ends visible.
Here I've stuck a piece of heavy duty tape to the ends of the canes to make them easier to see ... a cane in the eye is an awful thought!
On a lighter note, you could attach wine corks to the ends of the canes ... but you'll have to drink the wine first!
Another option is empty plastic vitamin containers placed upside-down on the ends of the canes.