Perhaps you should try some spelling variations:
thanh tam » thanh tai, thanh tay, thanh nam
va thanh » gia thanh, ban thanh, va tinh
kham duc » pham duc, kham cuoc, pham duy
tu sach » thu sach, su sach, te sach
tam cua » nam cua, lam cua, dam cua
hieu va » lieu va, hieu qua
hieu vu » hieu ve, hieu su, dieu vu
sach ty » sach y, sach tu, sach thu
mai hoi » mai khoi, dai hoi, lai hoi
ty tang » tay tang, ty xang, ty hang
cua tre » cua te, cuu tre, cua triet
ma hoi » xa hoi, ma hoa, me hoi

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 ty tang ((ma hoi) or (mai hoi)). ((hieu vu) OR (hieu va)) kham duc va thanh tam cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ty tang ((ma hoi) OR (mai hoi)). ((hieu vu) OR (hieu va)) kham duc va thanh tam cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ty tang ((ma hoi) or (mai hoi)). ((hieu vu) OR (hieu va)) kham duc va thanh tam cua tre".
• Adding a wildcard symbol may retrieve word variants: tu sach ty tang ((ma hoi) or (mai hoi)). ((hieu vu) OR (hieu va)) kham duc va thanh tam cua tre*.