I'm Struggling to Understand Korean Sentences Despite Knowing the Words

Hi, I need some help...

I was sentence mining from a drama, and when I watched the same episode I had mined words from, I realized that, other than the advanced words that were normal for me not to understand, I wasn't understanding the gap between the words (the vocabulary I knew felt isolated). I wasn't understanding the grammar and the particular meaning of the sentence (sometimes idioms and phrases). Even for sentences where I knew every word, what I understood was close to the actual meaning, but not what my native subs said—it was nowhere near that.

I want to fill that gap. Setting the advanced and uncommon words aside, I want to understand the whole sentence (together).

Here's my background in Korean: - I went through Sogang Korean books 1 to 3. - I've created Anki cards for TTMIK's grammar lessons (books 1 to 6) (my cards sucked, so I only went through them once). - I've mined 2,300 words through watching dramas/reality shows.

I was thinking of either using dual subs (EN & KO) to see how those missing gaps are filled, or studying the grammar (my Anki cards or a textbook, or perhaps any other approach you recommend).

Any ideas, answers, or experiences similar to mine are welcome and appreciated. Feel free to ask questions to clarify.