Perhaps you should try some spelling variations:
sach ky » sac ky, sach ty, sach kem
lang xa » lang ha, dang xay, lang van
hieu va » lieu va, hieu qua
cach tu » cach thuc
va hanh » van hanh, va thanh, va danh
cu tren » tu tren, dua tren
cac tu » cac thu, cac du, tac tu
vi cu » vi su, vi xu, vi du

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

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