I live in Isaan and have noticed that since 4 or 5 months my modem (TOT) disconnects from the internet for around 10 to 15 minuets before reconnecting,this happens about 6 times a day,some days are better than others,anyone know why ?

Most likely a poor connection if ADSL on a phone line - check the signal to noise and capability of your connection in your modem - a good PM would be to go to phone line connection into house and clean/tighten that as it often can cause intermittent issues if a poor connection. Also be sure an adsl/phone splitter is good.

Yes, most likely you have a poor local physical line connection.