Bought or brought:
Bought: past tense and past participle of verb to buy - Gain possession of by giving money; obtain by payment; purchase; obtain in exchange for something else, or by making a sacrifice; win over, hire or engage (usually in a bad sense as in: winning favour by using money, influence, bribing; suffer, be wounded, killed, or destroyed; believe; accept; approve.
Brought: past tense and participle of verb to bring - Cause to come with, or to convey by carrying, leading, impelling or attracting; to prefer a charge, initiate legal action.
There should be little difficulty with this one if you keep in mind the relationship between ‘bought’ and ‘buy’. Something that has been bought is a thing that has been purchased.
When you use ‘brought’, it is describing the action of bringing something from one place to another. I don’t know, but perhaps if you remember that the ‘r’ in ‘brought’ stands for ‘retrieve’, it might help as a mnemonic.