Perhaps you should try some spelling variations:
sach ty » sach tu, sach thu, xach tay
xang xa » lang xa, mang xa, ang xa
hieu va » lieu va, hieu qua
vuc van » luc van, thuc van, chuc van
duc van » duc va, duc tan, duc manh
dinh vi » dinh ve, dinh viet, dinh tri
vi cua » vai cua, di cua
cua tu » cua tuc, cua su, cua cu

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 ty) OR (sach y)) xang xa hoi. hieu va cac ((vuc van) or (duc van)) dinh vi cua tu~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su ((sach ty) OR (sach y)) xang xa hoi. hieu va cac ((vuc van) OR (duc van)) dinh vi cua tu.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su ((sach ty) OR (sach y)) xang xa hoi. hieu va cac ((vuc van) or (duc van)) dinh vi cua tu".
• Adding a wildcard symbol may retrieve word variants: su ((sach ty) OR (sach y)) xang xa hoi. hieu va cac ((vuc van) or (duc van)) dinh vi cua tu*.