This is the 7782nd most frequent Chinese word.
開主
"開主" does not appear to be a standard or common Chinese word or phrase. It might be a typo or a less common usage.
In this sentence, '開主' metaphorically means enlightening or inspiring one's own mind.
這本書的內容非常深刻，讓我開主自己的思想。
The content of this book is very deep, it opens my own thoughts.
Here, '開主' conveys the meaning of instructing or guiding students to think in a certain direction.
老師開主我們讨论问题时必须考虑多个角度。
The teacher instructed us to consider multiple perspectives when discussing issues.
'開主' in this context refers to the idea of fostering or developing skills and abilities.