Perhaps you should try some spelling variations:
ve triet » va trien, su triet
hoi dong » hop dong, hoat dong, ha dong
cam thuc » am thuc, nam thuc, cam thu
hieu van » hieu va, thien van, lieu va
hoi dang » hoi dan, hoi lang, hoi dung
hai dang » hai bang, dai dang, hai duong
van cam » van nam, van lam, van cau
thuc va » thuc vat, thuc dan, thuc day
va dinh » van dinh, va kinh, va tinh
dinh ve » dinh ket, dinh van
vu sach » vu bach, su sach, vu khach
ve ve » de ve, va ve, ke ve

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

• Performing a fuzzy search may retrieve terms with similar spellings: vu sach ((((hoi dang) OR (hai dang))) or (hoi dong)) xa hoi. hieu van cam thuc va dinh ve ve triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: vu sach ((((hoi dang) OR (hai dang))) OR (hoi dong)) xa hoi. hieu van cam thuc va dinh ve ve triet*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "vu sach ((((hoi dang) OR (hai dang))) or (hoi dong)) xa hoi. hieu van cam thuc va dinh ve ve triet*".