Perhaps you should try some spelling variations:
sach le » cach le, sach de, sach lo
va hanh » van hanh, va thanh, va danh
bac luc » bao luc
van bac » van ban, van bao, van hac
so sach » so sanh, bo sach, co sach
quang y » quan y, quang _, quang d
quang x » quang _, quang d, quang xuc
thi van » thi lan, thi hanh, thi nang
luc va » duc va, tuc va, loc va
vi cau » va cau, ve cau, viet cau
di cau » da cau, diem cau

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 le ((quang x) or (quang y)) ho. thi van bac luc va hanh ((vi cau) OR (di cau)) treo~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so sach le ((quang x) OR (quang y)) ho. thi van bac luc va hanh ((vi cau) OR (di cau)) treo.
• The words AND, OR and NOT may confuse the search; try adding quotes: "so sach le ((quang x) or (quang y)) ho. thi van bac luc va hanh ((vi cau) OR (di cau)) treo".
• Adding a wildcard symbol may retrieve word variants: so sach le ((quang x) or (quang y)) ho. thi van bac luc va hanh ((vi cau) OR (di cau)) treo*.