How to use index efficiently in SQL (Oracle)

SELECT /*+ INDEX(GMS_TSP_PROPOSE GMS_TSP_PROPOSE_IDX1)  */

        DISTINCT SUBSTR(TSP_BL_NUMBER,5) AS TSP_BL_NUMBER,

                        TSP_FINAL_DESTINATION,

                        TSP_REFNO,

                        TSP_BL_REFNO,

                        VESSEL_NAME,

                        TSP_VOYAGE,

                        TSP_PORT

        FROM GMS_TSP_PROPOSE, GMS_VESSEL_MASTER

 WHERE TSP_STATUS = 'P' AND

       TSP_Vessel = VESSEL_CODE

 

Note: Never use Table Alias in SQL with will not allow to use index.