In countries that LEGO has a Lego Brand Retail store (eg UK, US, Germany) , they normally also have a website which sells Lego directly. This is known as the LEGO Shop@Home site. The Shop@Home site also operates in certain select countries which do not have a LBR like Australia and South Korea.
For countries which run with the LEGO CERTIFIED STORE scheme like Singapore and Malaysia, this Shop@Home is missing and many have wondered if it will ever reach our shores with rumours in the last few years that LEGO is working in that direction. Wonder no more as that does not seem to be happening, as of 14th October 2017, LEGO has announced an official shop @ the Lazada site (Lazada is an e-commerce site owned by the Ali Baba Group)
Selection looks to be quite limited at the moment and time will tell if Lazada will get access to LCS Exclusive sets too (quite a low probability of that happening)
The good news to consumers is that Lazada runs quite a lot of discount codes and coupons from time to time so they will be able to utilize the coupons for their LEGO purchases too.
Here are the links to the shop fronts