I see a few mistakes just from glancing through. Well, not really mistakes but more like awkward phrasing that could be rearranged to sound better.
It's a major distraction and the biggest troublemaker life could throw at her, in addition to all the other so-called obstacles, hurled in her way.
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In addition to all the other so-called obstacles hurled in her way, it's the biggest troublemaker life could throw at her,
Explanation: Firstly, you don't need so many commas. Rearranging it would make it read smoother. Secondly, leave it brief. Basically, you should be aiming to cut out any unnecessary phrases. If love is already a troublemaker, the reader can interpret it as a distraction-- or they can find it out in the story itself. You don't need it to add to your word count when a reader's attention span is only so small. And if you do need it, just replace troublemaker with distraction.
This aunty isn’t interested in anybody!
Cheng Meiqi wished to live without love. As a student from Generation studying chemistry and a graduate of the rest of science majors, her entire self could be described in a single sentence.
Blockhead who only needed science.
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This aunty, Cheng Meiqi, isn’t interested in anybody!
As a student studying chemistry and a graduate of the rest of science majors, her entire self could be described in a single sentence:
A blockhead who only needed science.
Explanation: Again, for the point of brevity, you can eliminate the entire second sentence. By saying that she wasn't interested in anybody automatically means that she wished to live without love. The introduction of her character was also a little awkward, so incorporating it in the first sentence helped it in becoming smoother. Also, again, details like the school she went to can be saved for the story itself. Keep the synopsis brief! For a smoother transition, I exchanged the period at the "...described in a single sentence" to a colon too.
And so…what was she doing?
"Make sure I have the same schedule as him."
"Pull some strings, I want to enter his company as his secretary."
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Yet… what was she doing?
"Make sure I have the same schedule as him."
"Pull some strings, I want to enter his company as his secretary."
Explanation: Following this sentence, you start talking about the fact that she still wanted to stay away from love. Therefore, it shouldn't be an "and" but a "yet" instead. Also, take note that after an ellipsis, there should be a space. Dialogue is fine.
Don’t take this the wrong way that she was doing this due to attraction. It was the opposite. She swore to her heart. She did this to eradicate all attachment towards that man. After all, she had promised to live without love!
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Don’t take it the wrong way! She was not doing this due to attraction. In fact, it was the opposite. She did this to eradicate all attachment towards that man. After all, she promised to live without love!
Explanation: The first sentence was very clunky and awkward. I had to read through it a second time to understand what you were trying to say. Usually, the phrase "don't take this the wrong way" should be used by itself, and adding onto it just makes it confusing. So, splitting the two is a good idea. Adding on the "in fact" to the next sentence makes the flow better. No need for the "she swore to her heart". It's another phrase that clutters up the synopsis. Removing "had" also simplifies it.
Hence, no one was to ask why she had a scientific journal detailing her mission to detach any romantic feelings for him. She wasn’t experiencing any increase in serotonin because of thinking of that man, not at all! Why would she think about him?
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No one was to ask why she had a scientific journal detailing her mission to shatter any romantic feelings for him. She wasn’t experiencing any increase in oxytocin because of thinking of that man. Not at all! Why would she think about him?
Explanation: Hence makes it seem like you're trying to write some academic essay or archaic writing that this story shouldn't be. Would rec replacing the word "detach" since you already talked about attachment the previous paragraph and the repetitive "tach" sound just sounds really bad when you read it out loud. I like "shatter" since it sounds romantic but "annihilate" or "demolish" or "extinguish" gives it a nice dramatic tone.
Also, why are you talking about serotonin? The only reason why I know about that chemical is because of depression meds. Is this girl depressed or something? Did some quick research and serotonin also causes nausea and lack of arousal. idk if those things are what you want your character to have. The love hormone is actually oxytocin. (Though then again, if you've actually done better research than me, feel free to correct me.) Would also rec to break up that run-on sentence you have going on with the "not at all", just for smoother flow.
“Miss Cheng, this is?” Jiang Minghao waved his hand holding her notebook.
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“Miss Cheng, this is?” Jiang Minghao waved his hand, holding her notebook.
Explanation: Gerund phrases (aka the -ing phrase) need commas.
The rest of your synopsis is good. Hope this helps! All in all, you just needed to fix some really basic issues as well as making it briefer. Your synopsis shouldn't be that long because your readers came to read your story, not your synopsis. The synopsis is merely a guide leading the reader to the story, where they will gain the information and actual content.