Perhaps you should try some spelling variations:
nham thuc » nhan thuc, nam thuc, nham thu
ban thanh » ban hanh, ban hang
cham truc » cau truc, pham thuc, nam truc
hieu van » hieu va, thien van, lieu va
thanh di » thanh doi, thanh de, thanh do
so sach » so sanh, bo sach, co sach
sach vu » sach va, sach tu, sach uu
hieu ve » hieu va
nang ma » tang ma, sang ma, nang cao
vu nang » vuc nang, va nang, vu dang
di cua » dai cua, doi cua, de cua
cua te » cua tu

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: so sach vu nang ma hoa. ((hieu ve) OR (hieu van)) ((cham truc) or (nham thuc)) ban thanh di cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so sach vu nang ma hoa. ((hieu ve) OR (hieu van)) ((cham truc) OR (nham thuc)) ban thanh di cua te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "so sach vu nang ma hoa. ((hieu ve) OR (hieu van)) ((cham truc) or (nham thuc)) ban thanh di cua te".
• Adding a wildcard symbol may retrieve word variants: so sach vu nang ma hoa. ((hieu ve) OR (hieu van)) ((cham truc) or (nham thuc)) ban thanh di cua te*.