Lah is similar to The Fallen Leaf because :
-Psychological pain from FL lead
-Transformation identity
-Revenge on the culprits

Bad Romeo is similar to Yah Leum Chan :
-Teenage love separation through letter
-ML and FL meet again many years later
-ML revenge on FL

Bad Romeo is similar to Sai Roong because :
-teenage love story
-dramatic ML and FL separation through a misunderstood letter
-Broken hearted ML and FL
-Tragic events happen on ML
-FL thought ML died and does not forgives herself
-ML becomes strong man, comes back to take revenge on FL

Sapai Pateevat is similar to Sapai Jao Sua because the daughter-in-law / parent-in-law comic relationship.

Sai Roong is similar to Ya Leum Chan :
-Same FL
-Romance during teenage years
-Forced break up letter from FL
-Revenge from ML many years later with new identity

Kleun Cheewit is similar to Sai Roong because :
-FL is alcohoolic actress/model with harmful past
-FL hearts ML by killing is lover / sending a rupture letter
-ML takes revenge on FL
=> MELODRAMATIC !!!

Wan Sawart is extremely similar to Klin Kasalorng :
-In the past life, 2 identical twin sisters loving the same man
-The evil twin steals the man from the good twin and killed her
-The ML and evil twin reincarnates in the present life
-The good twin is still a gost to revenge the bad twin

Hong Hern is similar to Ga Gub Hong because the ML chooses the poor FL instead of the spoiled devil FL.

Sud Sai Pan is really similar to Song Naree :
-same plot
-twin sisters separate at birth
-older one raised by her father and nice girl
-younger one raised by her mother and bad girl
-male lead confused between the twin sisters identity

Rottanakosin is similar to Ka Badin because both are starring during Rottanakosin thai period and age gap between ML and FL.

Sai See Plerng is similar to Poisonous Passion because the main lead actress is a brillant woman who seduces several men.

Buang is similar to Paap Ataan because of the vengeful horror theme that involves an woman gost who doesn't want to end up with revenge on male lead and female lead and does not want to reincarnate.