Solution : https://service.sap.com/sap/support/notes/1559304 (SAP Service marketplace login required)
Key words : 
bc-db-ora note 176754, oracle cost-based optimizer, entire table swwwihead sequentially, full table scan, relevant oracle hint, reorganize work items, correction instructions add, relevant select statements, field swwwihead-wi_chckwi, index swwwihead~
Related Notes : 
       
| 176754 | Problems with CBO and RBO |