Perhaps you should try some spelling variations:
tham thuc » nham thuc, pham thuc, tam thuc
cham tuc » nham thuc, pham thuc, cham soc
te sach » toc sach
danh vi » hanh vi, dinh vi, danh di
va danh » va dinh, va dan, va hanh
hieu va » lieu va, hieu qua
tang ma » mang may, tang van
nang ma » sang ma, nang cao, mang may
sach v » sach va, sach y, sach 2
vi cua » vai cua, di cua

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

• If you are trying to use Boolean operators, they must be ALL CAPS: te sach v ((nang ma) OR (tang ma)) hoi. hieu va ((cham tuc) OR (tham thuc)) va danh vi cua vat~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach v ((nang ma) OR (tang ma)) hoi. hieu va ((cham tuc) or (tham thuc)) va danh vi cua vat~".
• Adding a wildcard symbol may retrieve word variants: te sach v ((nang ma) OR (tang ma)) hoi. hieu va ((cham tuc) or (tham thuc)) va danh vi cua vat*.