Perhaps you should try some spelling variations:
cua triet » cua viet, va triet
van khang » van khanh, van thanh, van quang
su triet » su viet, su tien, ve triet
cau thuc » cau truc, cuu thuc, can thuc
khang te » khang tiet, hang tu, khang a
thuc van » thuc vat, thuc dan, thuc va
hieu van » hieu va, thien van, lieu va
tu sach » thu sach, su sach, te sach
nang ma » tang ma, sang ma, nang cao
vu sach » vu bach, su sach, vu khach
van cau » van dau, van hau, van chat
ma hoi » mai hoi, xa hoi, ma hoa

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 (vu sach)) ky nang ma hoi. hieu van cau thuc van khang te ((cua triet) OR (su triet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (vu sach)) ky nang ma hoi. hieu van cau thuc van khang te ((cua triet) OR (su triet)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) or (vu sach)) ky nang ma hoi. hieu van cau thuc van khang te ((cua triet) OR (su triet))".
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (vu sach)) ky nang ma hoi. hieu van cau thuc van khang te ((cua triet) OR (su triet))*.