How to launder.....

Not sure this is the correct Forum--but it is the closest one..

Many of my summer tops have seriously yellow stains in the underarms.
I DO sweat a lot--as I DO work at a physical job-and do a lot of gardening at home.

I have tried soaking them in a Bleach solution with OxyClean powder for a couple days.
No change. I know it could be the deodorant I use-"Secret" is my favorite. Does it matter?

Long, long ago--I used to soak my tops in a Vinegar solution--and it seemed to work.
Does not work nowadays.

Any suggestions? Thanks, Gita