Perhaps you should try some spelling variations:
viec sach » viet sach, vien bach, dien sach
hieu viec » nhieu viec, hieu ve, sieu viet
sach nuoc » sach duoc, cac nuoc, bach tuoc
xanh doi » xanh di, thanh doi, tinh doi
vu sach » vu bach, su sach, vu khach
sach ky » sac ky, sach y, sach ty
nang ma » tang ma, sang ma, mang may
va xanh » va danh, va hanh, va anh
doi cua » dai cua, hoi cua
cua tre » cua te, cuu tre, cua triet

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 ky ((nang ma) or (nang cao)) hoi. hieu viec sach nuoc va xanh doi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: vu sach ky ((nang ma) OR (nang cao)) hoi. hieu viec sach nuoc va xanh doi cua tre.
• Adding a wildcard symbol may retrieve word variants: vu sach ky ((nang ma) or (nang cao)) hoi. hieu viec sach nuoc va xanh doi cua tre*.