Perhaps you should try some spelling variations:
va hanh » van hanh, va thanh, va danh
cam duc » cam xuc, cao duc, pham duc
hieu ve » hieu va, hieu van
nang ma » tang ma, sang ma, nang cao
sach va » sach xa, sach ha, sach dao
cua tre » cua te, cuu tre, cua triet
sach v » sach y, sach 2, sach vay
ve cam » ve cham, ve cac, va cam
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: te ((sach v) or (sach va)) ((nang x) or (nang ma)) hoi. hieu ve cam duc va hanh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te ((sach v) OR (sach va)) ((nang x) OR (nang ma)) hoi. hieu ve cam duc va hanh vi cua tre.
• Adding a wildcard symbol may retrieve word variants: te ((sach v) or (sach va)) ((nang x) or (nang ma)) hoi. hieu ve cam duc va hanh vi cua tre*.