Perhaps you should try some spelling variations:
su sach » so sach, vu sach
sach ty » sach y, sach tu, sach thu
ty nang » ky nang, ty xang, ty hang
cua tre » cua te, cuu tre, cua triet
va nay » va ngay, va cay
xuc va » duc va, tuc va, xac va
luc va » duc va, tuc va, loc va
vi cua » vai cua, di cua
o hoi » co hoi, o hoc, o hai

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 nang ((o hoi) or (xa hoi)). lieu va nay ((xuc va) OR (luc va)) hanh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ty nang ((o hoi) OR (xa hoi)). lieu va nay ((xuc va) OR (luc va)) hanh vi cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ty nang ((o hoi) or (xa hoi)). lieu va nay ((xuc va) OR (luc va)) hanh vi cua tre".
• Adding a wildcard symbol may retrieve word variants: su sach ty nang ((o hoi) or (xa hoi)). lieu va nay ((xuc va) OR (luc va)) hanh vi cua tre*.