Perhaps you should try some spelling variations:
tang mai » tang ma, tang tai, lang mai
hanh lam » thanh lap, hanh kem, dinh lam
cham duc » pham duc, cham soc, pham duy
su sach » so sach, vu sach
hanh va » hang va, hanh vi
hieu va » lieu va, hieu qua
sach ty » sach y, sach tu, sach thu
hieu vu » hieu ve, hieu su, dieu vu
mai hoi » mai khoi, dai hoi, lai hoi
ty tang » tay tang, ty xang, ty hang
cua tre » cua te, cuu tre, cua triet

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 tang mai hoi. ((hieu vu) OR (hieu va)) cham duc va ((hanh lam) or (hanh va)) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ty tang mai hoi. ((hieu vu) OR (hieu va)) cham duc va ((hanh lam) OR (hanh va)) cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ty tang mai hoi. ((hieu vu) OR (hieu va)) cham duc va ((hanh lam) or (hanh va)) cua tre".
• Adding a wildcard symbol may retrieve word variants: su sach ty tang mai hoi. ((hieu vu) OR (hieu va)) cham duc va ((hanh lam) or (hanh va)) cua tre*.