Perhaps you should try some spelling variations:
thuat sach » thuat lanh, thuat san
sach ky » sac ky, sach y, sach ty
nang xa » nang x, nang ma, mang xa
lang xa » lang ha, dang xay, lang van
hieu va » lieu va, hieu qua
va hanh » van hanh, va thanh, va danh
hai cua » thai cua, hoi cua, lai cua
cac lo » cac lop, cac co, cac bo
lo va » lo van, lao va, ly va

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

• Performing a fuzzy search may retrieve terms with similar spellings: thuat sach ky ((nang xa) OR (lang xa)) hoi. hieu va cac lo va hanh ((dai cua) or (hai cua)) tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thuat sach ky ((nang xa) OR (lang xa)) hoi. hieu va cac lo va hanh ((dai cua) OR (hai cua)) tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thuat sach ky ((nang xa) OR (lang xa)) hoi. hieu va cac lo va hanh ((dai cua) or (hai cua)) tre".
• Adding a wildcard symbol may retrieve word variants: thuat sach ky ((nang xa) OR (lang xa)) hoi. hieu va cac lo va hanh ((dai cua) or (hai cua)) tre*.