Regardless of the time of day you decide to fly, the ticket price will remain around the same. Book flights from Langkawi to Boracay as you normally would.
These are just IATA (International Air Transport Association) codes. They are used in aviation to identify and differentiate airports. That’s why a Langkawi Airport to Boracay Godofredo P. Ramos Airport flight would often be abbreviated as a LGK to MPH flight.