Perhaps you should try some spelling variations:
cham tuc » nham thuc, pham thuc, tham thuc
hieu van » hieu va, thien van, lieu va
cau tren » cu tren, dau tren, ca tren
nang co » nang cao, nang doc, nang noi
hieu ve » hieu va
sach ty » sach tu, sach thu, xach tay
va danh » va dinh, va dan, va hanh
danh ve » dinh ve, hanh ve, anh ve
tuc va » thuc va, truc va, tuc xa
ve cau » ke cau, va cau, ve cac

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

• Performing a fuzzy search may retrieve terms with similar spellings: thu ((sach ty) or (sach y)) nang co hoc. ((hieu ve) OR (hieu van)) cham tuc va danh ve cau tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu ((sach ty) OR (sach y)) nang co hoc. ((hieu ve) OR (hieu van)) cham tuc va danh ve cau tren.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu ((sach ty) or (sach y)) nang co hoc. ((hieu ve) OR (hieu van)) cham tuc va danh ve cau tren".
• Adding a wildcard symbol may retrieve word variants: thu ((sach ty) or (sach y)) nang co hoc. ((hieu ve) OR (hieu van)) cham tuc va danh ve cau tren*.