Perhaps you should try some spelling variations:
hieu quan » lieu quan, thien quan, lien quan
hanh thai » nhanh thai, hinh thai, hanh tai
thai cua » than cua, tai cuc, tri cua
van hanh » van thanh, ban hanh, van anh
su sach » so sach, vu sach
luc van » luoc van, luu van, duc van
cam luc » cam xuc, cau luc
cua tre » cua te, cuu tre, cua triet
sach ky » sac ky, sach y, sach ty
hieu ve » hieu va, hieu van
lang xa » lang ha, dang xay, lang van
ky lang » ky nang, ky dang, ky tang

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 lang xa hoi. ((((hieu ve) or (hieu qua))) or (hieu quan)) cam luc van hanh thai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ky lang xa hoi. ((((hieu ve) OR (hieu qua))) OR (hieu quan)) cam luc van hanh thai cua tre.
• Adding a wildcard symbol may retrieve word variants: su sach ky lang xa hoi. ((((hieu ve) or (hieu qua))) or (hieu quan)) cam luc van hanh thai cua tre*.