Perhaps you should try some spelling variations:
dinh vai » dinh van, dinh va, dinh tai
thu sac » thu sach, thu san, thu xac
nang ho » nang hoc, nang co, tang ho
hieu va » lieu va, hieu qua
dinh vi » dinh ve, dinh viet, dinh tri
cua tre » cua te, cuu tre, cua triet
sac ky » cac ky, sai ky
nang o » nang co, nang ro, nang x
cac lo » cac lop, cac co, cac bo
lo va » lo van, lao va, ly va

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

• Performing a fuzzy search may retrieve terms with similar spellings: thu sac ky ((nang o) or (nang ho)) hoi. hieu va cac lo va ((dinh vai) OR (dinh vi)) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sac ky ((nang o) OR (nang ho)) hoi. hieu va cac lo va ((dinh vai) OR (dinh vi)) cua tre*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sac ky ((nang o) or (nang ho)) hoi. hieu va cac lo va ((dinh vai) OR (dinh vi)) cua tre*".