If the oral antibiotics arent working you may need a couple rounds of the IV antibiotics. Hope you feel better soon :)
There are several bacterial resistant strains of typhoid that have developed. Continue your medication protocol and be in touch with your physician. It is likely he will prescribe another antibiotic. Augmentin may not be appropriate. Follow his advice. Drink grapefruit juice with the antibiotic.
Remember that antibiotics continue to work at least 10 days after you stop taking them. Maybe you haven't given it enough time. Make sure you take your meds as directed. Don't skip any doses!