Perhaps you should try some spelling variations:
cau tren » cu tren, dau tren, ca tren
danh hai » dang hai, lanh hai, manh hai
hieu van » hieu va, thien van, lieu va
thuc va » thuc vat, thuc dan, thuc day
hai cau » hai chau, hai chu, hai hau
so sach » so sanh, bo sach, co sach
sach ty » sach y, sach tu, sach thu
van lam » van nam
nang ma » tang ma, sang ma, nang cao
ty nang » ky nang, ty xang, ty hang
tuc va » truc va, tuc xa, duc va
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: so sach ty nang ma hoi. hieu van lam ((tuc va) or (thuc va)) danh hai cau tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so sach ty nang ma hoi. hieu van lam ((tuc va) OR (thuc va)) danh hai cau tren*.