Theorectically, most probiotics cannot survive stomach acid but the best kinds of probiotics in the market utilizes a technology that protects probiotics from stomach acid. However, most probiotics do not use this technology as it must be costly. Not too sure it yakult drinks utilize this technology. Many probiotics are merely marketing gimmicks or placebos so in a way, you definitely get what you pay for in probiotics.
To ensure probiotics survival, do not take them on an empty stomach as the benefit you are getting is very minimal at best; however, it is likely you may not be getting any benefit. If you take a probiotic at meal time, the food actually protects the probiotic from some of the stomach acid but still a lot gets destroyed as increased stomach acid is made during meal times.