Perhaps you should try some spelling variations:
sut triet » su triet, suat thiet, cua triet
hieu van » hieu va, thien van, lieu va
van pham » san pham, van phan, van phat
trinh do » trinh ky
tu sach » thu sach, su sach, tu cach
te sach » toc sach
tinh do » tinh doi, tinh da, kinh do
x hoi » xa hoi, o hoi, x ho

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((tu sach) or (te sach)) ky nang x hoi. hieu van pham duc va ((tinh do) OR (trinh do)) sut triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (te sach)) ky nang x hoi. hieu van pham duc va ((tinh do) OR (trinh do)) sut triet*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) or (te sach)) ky nang x hoi. hieu van pham duc va ((tinh do) OR (trinh do)) sut triet*".