Both dramas revolve around friends and their lives with each other and with their marriages. Especially one couple is very similar to the main couple of The World of the Married. Both females are doctors, both couples have sons, and both couples deal with conflicted feelings, with obsession and deceive, secrets and murder. But also the other couples have their respective drama and betrayals.
If you liked especially the female lead in The World of the Married, you will love Graceful Friends, for she is nearly the exact same person.

Flower of the Evil and Blood and Ties are both very dark and brutal dramas. Both deal about families where one member has a secret past tied to a crime and another member finding out about it. In both dramas this crime revolves around a murder.
In Blood and Ties it is however the daughter that is suspicious of her kind father, whereas in Flower of the Evil it is the wife that doubts her husband more and more.
Both dramas feel very similar.

Both dramas follow a similar concept: In Train we have someone who switches places with himself of another world, while in "Your Honor" a twin switches places. In both dramas there are cases that need to be solved. If you like the concept of the one drama, you will probably enjoy the other..

Although one is about time travel and another one is not, both dramas have lots of similarities with their respective cases. In both dramas we have a police team that has to deal with similar cases, and situations. Both main leads get help from a female lead who is not involved in the police department. Both cases are gripping and surprising and full of twists and turns one would not expect.

A mysterious detective partner duo, teaming up with a strong female lead. Corruption, cases being not what they seem to be, and police officers making mistakes. All are both themes in both dramas. So far, however, The Good Detective seems like the little sister to Watcher. If you enjoy The Good Detective you will adore Watcher.

Both dramas are about a married couple who is not married for love and both couples face difficult decisions and situations. Both dramas also have something to do with unfaithfulness and in both dramas we have very strong women who are willing to cross lines for their work. Both dramas are very, very, very mature and are so powerful that one has to stop often in order to keep on breathing.
Both dramas have also gotten an ending that robs one of all the last piece that was left while watching them.
They are masterpieces of no comparison.

Both dramas have mature themes and strong female and male leads.
Both deal around a similarish couple. In both dramas the circumstances are similar and the characters themselves are similar as well. While in "The World of the married" this specific thing happens to the main couple, in "Money Flower" it is a little more complicated. Interestingly in both dramas Han So Hee plays in both dramas the mistress.

Both leads are very similar when it comes to their character and both dramas are in general having a lot of similarities as well. Both deal about leads that suffered a devastating loss in their childhood, and both got shaped because of that. Both became police officers due to that and both are faced with a crime that hits very close to home.

The main story is basically the same. We have two married women that believe their husband is cheating with someone they are close with/work with. Both dramas are build up like a detective drama with the difference about not finding a murderer, but finding out who it is their husband is cheating with.

Both have a main lead who suffered from someone who is in a high position. Both male leads are very similar to their character. Both wish to get revenge and both make it by planing a very long time.
Generally both drama have a pretty similar story, however the biggest difference is the morales the main leads have.

Both dramas are having the same message: when you loose everything, don't give up, there will be a door that opens up. The only difference is that Bonus book finds that with publishing books and Touch is dealing about make-up. Also both have a couple that has an age gap, with Bonus book it is the female that is a bit older than the male, with Touch it is the male that is older than the female. Both pairings work with each other, in both dramas the male leads are the boss, the female leads are their employee. Generally both give off a very similarish feeling.

Just like The Game, Signal deals about murder cases and supernatural occurrences that help investigation teams solve them. While Signal does this with a walkie-talkie that connects the present to the past, The Game deals about someone who can see the death of people. Both try to solve cases with their unique ability. Also both resolve around cases that shape each main character. the cases that shape them are quite similar to one another as well however due to spoilers i cannot go deeper into this.
Signal is a masterpiece of masterpieces, The Game seems to go into a similar direction with it as well.