Perhaps you should try some spelling variations:
sach thue » sach thu, sach thieu, sach tham
truc van » truc va, thuc van, truc ban
van hanh » van thanh, ban hanh, van anh
xang xa » lang xa, mang xa, ang xa
va cau » van cau, va cac, va dau
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: su ((sach y) or (sach thue)) xang xa hoi. lieu va cau truc van hanh ((vi cua) OR (di cua)) tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su ((sach y) OR (sach thue)) xang xa hoi. lieu va cau truc van hanh ((vi cua) OR (di cua)) tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su ((sach y) or (sach thue)) xang xa hoi. lieu va cau truc van hanh ((vi cua) OR (di cua)) tre".
• Adding a wildcard symbol may retrieve word variants: su ((sach y) or (sach thue)) xang xa hoi. lieu va cau truc van hanh ((vi cua) OR (di cua)) tre*.