Perhaps you should try some spelling variations:
su sach » so sach, vu sach
va tinh » may tinh
cac xuc » cam xuc, cac nuoc, chat xuc
sach ky » sac ky, sach y, sach ty
hieu va » lieu va, hieu qua
lap lai » lap tai, lay lai, lam lai
lap hai » lap tai, lap hoat, lanh hai
ky sang » ky nang, ky dang, ky tang
xuc va » duc va, tuc va, luc va
di cua » dai cua, doi cua, do cua
de cua » le cua, te cua, dieu 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 ky sang ((lap hai) OR (lap lai)). hieu va cac xuc va tinh ((di cua) or (de cua)) te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ky sang ((lap hai) OR (lap lai)). hieu va cac xuc va tinh ((di cua) OR (de cua)) te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ky sang ((lap hai) OR (lap lai)). hieu va cac xuc va tinh ((di cua) or (de cua)) te".
• Adding a wildcard symbol may retrieve word variants: su sach ky sang ((lap hai) OR (lap lai)). hieu va cac xuc va tinh ((di cua) or (de cua)) te*.