Perhaps you should try some spelling variations:
hieu quan » lieu quan, thien quan, lien quan
hoc sach » hoc sinh, hoc anh
hanh gia » danh gia, thanh gian, hinh giao
van hanh » van thanh, ban hanh, van anh
gia cua » gian cua, giau cua, gia cuc
luc van » luoc van, luu van, duc van
cam luc » cam xuc, cau luc
cua tre » cua te, cuu tre, cua triet
hoc cac » hoc cao
sang ma » tang ma, nang ma, sang tao
ma hoi » mai hoi, xa hoi, ma hoa
v sang » va sang, ve sang, _ sang

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: ((hoc sach) or (hoc cac)) v sang ma hoi. ((hieu qua) or (hieu quan)) cam luc van hanh gia cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((hoc sach) OR (hoc cac)) v sang ma hoi. ((hieu qua) OR (hieu quan)) cam luc van hanh gia cua tre.
• Adding a wildcard symbol may retrieve word variants: ((hoc sach) or (hoc cac)) v sang ma hoi. ((hieu qua) or (hieu quan)) cam luc van hanh gia cua tre*.