Perhaps you should try some spelling variations:
sach tham » sach nha
xang van » dang van, tang van, nang van
lang van » dang van, tang van, hoang van
va hanh » van hanh, va thanh, va danh
cau luc » cau truc, cau phuc
so sach » so sanh, bo sach, co sach
hieu ve » hieu va, hieu van
ve cau » ke cau, va cau, ve cac
luc va » duc va, tuc va, loc va
vi cua » vai cua
di cua » dai cua, doi cua, de cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: so sach tham ((xang van) or (lang van)) hoe. hieu ve cau luc va hanh ((vi cua) OR (di cua)) viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so sach tham ((xang van) OR (lang van)) hoe. hieu ve cau luc va hanh ((vi cua) OR (di cua)) viet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "so sach tham ((xang van) or (lang van)) hoe. hieu ve cau luc va hanh ((vi cua) OR (di cua)) viet".
• Adding a wildcard symbol may retrieve word variants: so sach tham ((xang van) or (lang van)) hoe. hieu ve cau luc va hanh ((vi cua) OR (di cua)) viet*.