Perhaps you should try some spelling variations:
cua viet » ca viet, hoa viet, cua vat
cham tuc » nham thuc, pham thuc, tham thuc
hieu va » lieu va, hieu qua
cua cua » cua chua, ca cua, qua cua
tu sach » thu sach, su sach, te sach
nang ma » tang ma, sang ma, nang cao
hieu vu » hieu ve, hieu su, dieu vu
sach v » sach va, sach y, sach 2
ma hoi » mai hoi, xa hoi, ma hoa
va day » va dao, va dau, va dai
va dap » va dao, va dau
v nang » va nang, vu nang, van nang

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 v nang ma hoi. ((hieu vu) or (hieu va)) cham tuc ((va day) OR (va dap)) cua cua viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach v nang ma hoi. ((hieu vu) OR (hieu va)) cham tuc ((va day) OR (va dap)) cua cua viet*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach v nang ma hoi. ((hieu vu) or (hieu va)) cham tuc ((va day) OR (va dap)) cua cua viet*".