Perhaps you should try some spelling variations:
hieu viec » nhieu viec, hieu ve, sieu viet
dan hang » ban hang, van hang, dat hang
dua tren » dung tren
viec lam » viec va
lam thuc » lam thuoc, am thuc, nam thuc
thuc dan » thuc hanh, hoc dan, thuc vat
hang di » hang doi, hang vi, hang dien
cua tre » cua te, cua triet, cua thep
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
lang xa » lang ha, dang xay, lang van
ky lang » ky nang, ky dang, ky tang
cuu tre » cau tren, cau treo

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 ky lang xa hoi. hieu viec lam thuc dan hang di ((((cua tre) OR (dua tren))) or (cuu tre))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky lang xa hoi. hieu viec lam thuc dan hang di ((((cua tre) OR (dua tren))) OR (cuu tre)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ky lang xa hoi. hieu viec lam thuc dan hang di ((((cua tre) OR (dua tren))) or (cuu tre))".
• Adding a wildcard symbol may retrieve word variants: tu sach ky lang xa hoi. hieu viec lam thuc dan hang di ((((cua tre) OR (dua tren))) or (cuu tre))*.