Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
su sach » so sach, vu sach
sach ty » sach y, sach tu, sach thu
ty nang » ky nang, ty xang, ty hang
nang ma » tang ma, sang ma, nang cao
truc va » thuc va, trung va
hanh va » hang va, hanh vi
va chua » vua chua, ca chua, va chu
chua te » cua te, chua tu, chua xe
ma hoi » mai hoi, xa hoi, ma hoa

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

• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ty nang ma hoi. hieu van nam ((truc va) OR (thuc vat)) hanh va chua te~.
• Adding a wildcard symbol may retrieve word variants: su sach ty nang ma hoi. hieu van nam ((truc va) or (thuc vat)) hanh va chua te*.