Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
hieu van » thien van, lieu va, hieu ve
van hang » van khang, van hoang, van thang
thuc van » thuc vat, thuc dan, thuc va
cau thuc » cau truc, cuu thuc, can thuc
hang tu » hoang tu, thang tu, hanh tu
hieu va » lieu va, hieu qua
tu sach » thu sach, su sach, te sach
nang ma » tang ma, sang ma, nang cao
vu sach » vu bach, su sach, vu khach
ma hoi » mai hoi, xa hoi, ma hoa
tu cua » hu cua, vu cua

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) OR (hieu va)) cau thuc van hang tu cua 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) OR (hieu va)) cau thuc van hang tu cua 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) OR (hieu va)) cau thuc van hang tu cua triet".
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (vu sach)) ky nang ma hoi. ((hieu van) OR (hieu va)) cau thuc van hang tu cua triet*.