Tom khlong is a traditional Thai dish similar to tom yum except that it uses herbs which have been dried or roasted. There is an alternative name that ancient Thai people had for tom khlong called tom hok ue (Thai: ต้มโฮกอือ, pronounced [tôm hôːk ʔɯ̄ː]; Hok ue is the sound that people make when take a sip) because the moment you take a sip it will produce a refreshing feeling.
There are various types of herbs in tom khlong depending on how you cook it but the most important ingredients are dried fish, any variety of dried fish (sometimes fresh fish are used); galangal, which is used to deodorize fishy smell; Kaffir lime leaves, also used to deodorize fishy smell; Lemon grass, Shallot, and Dry Thai chili peppers. Also, paprika can be added for extra spice. Other ingredients are also sometimes added to bring more flavour and texture, such as lime juice, Tomatoes, Basil and Parsley.