Perhaps you should try some spelling variations:
hieu viec » nhieu viec, hieu ve, sieu viet
van thanh » ban thanh
viec ban » viec lam, viec va, viec tai
ban tuoc » ban thuoc, ban duoc, ban tuong
van tuan » van quan, van ban, anh tuan
tu sach » thu sach, su sach, te sach
sach ty » sach y, sach tu, sach thu
nang ho » nang hoc, nang co, tang ho
cua tre » cua te, cuu tre, cua triet
nang o » nang co, nang ro, nang x
co cua » con cua, ca cua, cong 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 ty ((nang o) OR (nang ho)) hoc. hieu viec ban tuoc ((van thanh) or (van tuan)) co cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ty ((nang o) OR (nang ho)) hoc. hieu viec ban tuoc ((van thanh) OR (van tuan)) co cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ty ((nang o) OR (nang ho)) hoc. hieu viec ban tuoc ((van thanh) or (van tuan)) co cua tre".
• Adding a wildcard symbol may retrieve word variants: tu sach ty ((nang o) OR (nang ho)) hoc. hieu viec ban tuoc ((van thanh) or (van tuan)) co cua tre*.