If you write the word "Shenyang", it means Shenyang Station, the old Shenyang South Station, and now it is called Shenyang Station, near Taiyuan Street and Nanyi Road.
If you write "Shenyang North", it means Shenyang North Station, near Shenyang Gong Hui Square.
If you write "Shenyang South", it is now Shenyang South Railway Station, in Sujiatun District of Shenyang, but now there are not many buses in Shenyang South Railway Station, mostly trucks.