This is the 364th most frequent Vietnamese word.
lưới
"Net" or "mesh."
In this sentence, 'lưới' refers to fishing net, a tool made of mesh material to catch fish.
Người ta dùng lưới để bắt cá.
People use nets to catch fish.
Here, 'lưới' describes the mesh material used in window screens.
Con mèo leo lên trên lưới cửa sổ.
The cat climbed onto the window screen.
In this context, 'lưới' denotes the net of a soccer goal, used in sports.