Technically yogurt is a live culture, however the one your looking for to help with the feminine issue is yogurt with bacterial cultures in it called "Probiotics". Another one will have a culture called BL Regularis.
By the way the probiotics will not cure a thing. They are mainly regarded as a benefit to the body but not something that should be considered a complete defensive mechanism. But having a simple cup of yogurt a day is sure a tasty way (I do not like yogurt personally) to boost your immune system even if it is only a little.