What type of bills covered in LTA?

Only the travel costs, not the eating and partying or hotel bills.
So, whether you fly, hop on to a train or take public transport, you can show the ticket and claim your LTA.
What if you want to travel by a car? If a car is owned by a central government organization like ITDC, the state government or the local body, LTA is permitted.
If you could not get public transport and resorted to private transport, try and get a bill. If the bill is not accepted by your employer, you can always file an income tax return, claim an exemption and get a refund.