My Wife Had Gall Bladder Surgery In February To Remove

My wife had gall bladder surgery in February to remove the gall bladder due to gallstones. Prior to the removal she had severe stomach and back pain and never knew when she might have to go to the bathroom with a bowel movement.
Following the surgery she experienced about a month where the conditions had receded. Now however she is experiencing the same symptoms as before and they basically cause her to be unable to function normally. Stomach pain, gas, backache without determining a correlation to foods that were consumed. Her primary care physician just said it is normal and her body needs to make adjustments but she is not able to predict when or why she will have an attack and this precludes from performing her daily routine. Any suggestions on what she should do or a specialist she should go to?? Thank you for your reply in advance.