Snakes aren't all the same, even the same species. The boa I had did not like to soak, & as far as I know, it's not typical behavior for boas. Since you just got her,
I hope you're keeping her on paper towels for substrate (temporarily) so you can make sure she doesn't have mites. I hate to tell you this, but soaking in water is
a typical snake response (snakes of all kinds) when they have mites, & since mites will kill a snake, it's important to make sure yours is not harboring them. If she
is, you'll need to eradicate them as soon as possible...their bites cause itching & irritation, but also dehydration & eventually shock & organ failure. If you house a
new snake on white plain paper towels for a while, mites that may drop off are easier to see. Also check the water bowl, & the snake itself.