Perhaps you should try some spelling variations:
tham thuc » nham thuc, pham thuc, tam thuc
cham tuc » nham thuc, pham thuc, cham soc
danh vi » hanh vi, dinh vi, danh di
va danh » va dinh, va dan, va hanh
vu sach » vu bach, su sach, vu khach
nang ma » tang ma, sang ma, nang cao
lang ha » long ha
cua tre » cua te, cuu tre, cua triet
vi cua » vai cua, di cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: vu sach y ((lang ha) or (nang ma)) hoi. hieu qua ((cham tuc) OR (tham thuc)) va danh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: vu sach y ((lang ha) OR (nang ma)) hoi. hieu qua ((cham tuc) OR (tham thuc)) va danh vi cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "vu sach y ((lang ha) or (nang ma)) hoi. hieu qua ((cham tuc) OR (tham thuc)) va danh vi cua tre".
• Adding a wildcard symbol may retrieve word variants: vu sach y ((lang ha) or (nang ma)) hoi. hieu qua ((cham tuc) OR (tham thuc)) va danh vi cua tre*.