Perhaps you should try some spelling variations:
viec bach » vien bach, viec ban, viec bao
bach tuoc » sach duoc, sach nuoc
van thanh » ban thanh
hieu viec » nhieu viec, hieu ve, sieu viet
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 co » nang cao, nang doc, nang noi
cua tre » cua te, cuu tre, cua triet
nang o » nang ho, 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 co)) hoc. hieu viec bach 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 co)) hoc. hieu viec bach 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 co)) hoc. hieu viec bach tuoc ((van thanh) or (van tuan)) co cua tre".
• Adding a wildcard symbol may retrieve word variants: tu sach ty ((nang o) OR (nang co)) hoc. hieu viec bach tuoc ((van thanh) or (van tuan)) co cua tre*.