Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
thu sach » tu sach, thuat sach, thuoc sach
toc sach » hoc sach, doc sach, thuoc sach
dieu cua » dieu tra
duc van » duc va, duc manh, duc phan
hang di » hang doi, hang vi, hang dien
nang o » nang co, nang ho, nang ro
di cua » dai cua, doi cua, de cua
o hoi » co hoi, o hoc, o hai

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((thu sach) or (toc sach)) ky nang o hoi. dieu cua cac ((duc van) or (duc tan)) hang di cua triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((thu sach) OR (toc sach)) ky nang o hoi. dieu cua cac ((duc van) OR (duc tan)) hang di cua triet.
• Adding a wildcard symbol may retrieve word variants: ((thu sach) or (toc sach)) ky nang o hoi. dieu cua cac ((duc van) or (duc tan)) hang di cua triet*.