Perhaps you should try some spelling variations:
"toc sach hoc lam nguoi" » "toc sach hoc tay nguoi", "hoc sach hoc lam nguoi", "doc sach hoc lam nguoi", "thuoc sach hoc lam nguoi", "toc cach hoc lam nguoi", "toc sach hoi lam nguoi", "toc sach duoc lam nguoi"
"toc mach hoc dao nguoi" » "toc mach hoc cho nguoi", "hoc mac hoc dao nguoi", "tim mach hoc dao nguoi", "tao mach hoc dao nguoi", "toc cach hoc dao nguoi", "toc dich hoc dao nguoi", "toc anh hoc dao nguoi", "toc mach hoc cao nguoi", "toc mach hoc dai nguoi", "toc mach toc dao nguoi"
"toc mach hoc dan nguoi" » "toc mach hoc den nguoi", "toc mach hoc ban nguoi", "toc mach hoc dan nuoi", "hoc mac hoc dan nguoi", "tim mach hoc dan nguoi", "tao mach hoc dan nguoi", "toc cach hoc dan nguoi", "toc dich hoc dan nguoi", "toc anh hoc dan nguoi"

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

• Performing a fuzzy search may retrieve terms with similar spellings: (("toc sach hoc lam nguoi") or ((("toc mach hoc dao nguoi") OR ("toc mach hoc dan nguoi"))))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("toc sach hoc lam nguoi") OR ((("toc mach hoc dao nguoi") OR ("toc mach hoc dan nguoi")))).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"toc sach hoc lam nguoi\") or (((\"toc mach hoc dao nguoi\") OR (\"toc mach hoc dan nguoi\"))))".
• Removing quotes may allow a broader search: (( toc sach hoc lam nguoi ) or ((( toc mach hoc dao nguoi ) OR ( toc mach hoc dan nguoi )))).
• Adding a wildcard symbol may retrieve word variants: (("toc sach hoc lam nguoi") or ((("toc mach hoc dao nguoi") OR ("toc mach hoc dan nguoi"))))*.