Perhaps you should try some spelling variations:
"su sach trinh cong khi đong luc" » "su sach trinh dung khi đong luc", "su sach tranh cong khi đong luc", "su hanh trinh cong khi đong luc", "su sach kinh cong khi đong luc", "su sach trinh cong thai đong luc", "su sach trinh khong khi đong luc", "su sach trinh co khi đong luc", "so sach trinh cong khi đong luc", "vu sach trinh cong khi đong luc"
"su sach danh cho khi đong luc" » "su sach tranh cho khi đong luc", "su sach dao cho khi đong luc", "su sach dung cho khi đong luc", "so sach danh cho khi đong luc", "vu sach danh cho khi đong luc", "su sach danh co khi đong luc", "su sach danh cho ghi đong luc", "su sach danh cao khai đong luc"

Try widening your search to All Fields.

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: (("su sach danh cho khi đong luc") or ("su sach trinh cong khi đong luc"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("su sach danh cho khi đong luc") OR ("su sach trinh cong khi đong luc")).
• Removing quotes may allow a broader search: (( su sach danh cho khi đong luc ) or ( su sach trinh cong khi đong luc )).
• Adding a wildcard symbol may retrieve word variants: (("su sach danh cho khi đong luc") or ("su sach trinh cong khi đong luc"))*.