Perhaps you should try some spelling variations:
sach ky » sac ky, sach y, sach kem
sach ty » sach y, sach tu, sach thu
lang ha » long ha
hieu va » lieu va, hieu qua
cua tre » cua te, cuu tre, cua triet
ha hoi » hoa hoi, ha noi, xa hoi
va cam » va cham, va cac, va cao
vi cua » vai cua, di 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) OR (sach ty)) lang ha hoi. hieu va cam ((tuc xa) or (duc va)) hanh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su ((sach ky) OR (sach ty)) lang ha hoi. hieu va cam ((tuc xa) OR (duc va)) hanh vi cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su ((sach ky) OR (sach ty)) lang ha hoi. hieu va cam ((tuc xa) or (duc va)) hanh vi cua tre".
• Adding a wildcard symbol may retrieve word variants: su ((sach ky) OR (sach ty)) lang ha hoi. hieu va cam ((tuc xa) or (duc va)) hanh vi cua tre*.