Perhaps you should try some spelling variations:
sach ky » sach y, sach ty, sach kem
nang ma » tang ma, sang ma, nang cao
luc van » luoc van, luu van, duc van
cua tre » cua te, cuu tre, cua triet
sac ky » cac ky, sai ky
ma hoi » mai hoi, xa hoi, ma hoa
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: tu ((sach ky) OR (sac ky)) nang ma hoi. lieu va cam ((luc van) or (duc tan)) hanh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach ky) OR (sac ky)) nang ma hoi. lieu va cam ((luc van) OR (duc tan)) hanh vi cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu ((sach ky) OR (sac ky)) nang ma hoi. lieu va cam ((luc van) or (duc tan)) hanh vi cua tre".
• Adding a wildcard symbol may retrieve word variants: tu ((sach ky) OR (sac ky)) nang ma hoi. lieu va cam ((luc van) or (duc tan)) hanh vi cua tre*.