Perhaps you should try some spelling variations:
thuat sach » thuat lanh, thuat san
cau tren » cu tren, dau tren, ca tren
nang ma » tang ma, sang ma, mang may
hieu ve » hieu va, hieu van
cac loc » cac lop, cac toc, cac hoc
va danh » va dinh, va dan, va hanh
danh ve » dinh ve, hanh ve, anh ve
te sach » toc sach
ve cac » va cac, vien cac
loc va » hoc va, luc va
ve cau » ke cau, va cau, le cau

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((te sach) or (thuat sach)) ky ((nang ma) or (nang cao)) hoi. hieu ve cac loc va danh ve cau tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((te sach) OR (thuat sach)) ky ((nang ma) OR (nang cao)) hoi. hieu ve cac loc va danh ve cau tren.
• Adding a wildcard symbol may retrieve word variants: ((te sach) or (thuat sach)) ky ((nang ma) or (nang cao)) hoi. hieu ve cac loc va danh ve cau tren*.