Perhaps you should try some spelling variations:
nhieu viec » hieu viec, nhien viet
chua tri » chu tri, chua trieu, chua tivi
chua tre » cua tre, chua trieu, cho tre
thu sach » thuat sach, thuoc sach, thu hoach
viec cac » vien cac, viec cua, viec lam
va nang » van nang, da nang, cam nang
nang ca » nang cao, nang cap, nang cai
tu sach » su sach, te sach, tu cach
tang ma » mang may, tang van
cac dac » cac dan, cac dai, cac bac
dac va » duc va, day va, dat va
y tang » ky tang, 6 tang, 7 tang

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) OR (thu sach)) y tang ma hoa. nhieu viec cac dac va nang ca ((chua tre) or (chua tri))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (thu sach)) y tang ma hoa. nhieu viec cac dac va nang ca ((chua tre) OR (chua tri))*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) OR (thu sach)) y tang ma hoa. nhieu viec cac dac va nang ca ((chua tre) or (chua tri))*".