What jabs do i need for a month in Thailand?

Definitely get your Hep B jabs. Might as well grab Hep A too. Grab a Typhoid vac. Get a Tet and Polio jab if you haven't received one in over 10 years. If you're planning on sleeping in cheap guest houses or tight quarters, feel free to take HiBs and meningicoccal vaccines if you'd like. Might as well get them anyways.