Perhaps you should try some spelling variations:
nang lai » nang tai, mang lai, nang cai
hanh dao » lanh dao, thanh dat, thanh dam
sach ky » sac ky, sach y, sach kem
dao cua » dai cua, day cua, dan cua
va hanh » van hanh, va thanh, va danh
cam tuc » cam xuc, cam tu, nam thuc
hieu va » lieu va, hieu qua
cua tre » cua te, cuu tre, cua triet
hieu ve » hieu van
lai hoa » dai hoa, loai hoc
sach ty » sach y, sach tu, sach thu
tuc va » thuc va, truc va, tuc xa

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 ky) OR (sach ty)) nang lai hoa. ((hieu ve) or (hieu va)) cam tuc va hanh dao cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so ((sach ky) OR (sach ty)) nang lai hoa. ((hieu ve) OR (hieu va)) cam tuc va hanh dao cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "so ((sach ky) OR (sach ty)) nang lai hoa. ((hieu ve) or (hieu va)) cam tuc va hanh dao cua tre".
• Adding a wildcard symbol may retrieve word variants: so ((sach ky) OR (sach ty)) nang lai hoa. ((hieu ve) or (hieu va)) cam tuc va hanh dao cua tre*.