Perhaps you should try some spelling variations:
hanh tai » thanh tai, hang tai, han tai
hieu van » hieu va, thien van, lieu va
tai cua » thai cua, tai cuc, tri cua
va hanh » van hanh, va thanh, va danh
hieu ve » hieu va
cua tre » cua te, cuu tre, cua triet
nang ma » tang ma, sang ma, nang cao
ma hoi » mai hoi, xa hoi, ma hoa
sach v » sach va, sach y, sach vay
soc va » hoc va, loc va, doc va
sach 2 » sach y

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 2)) nang ma hoi. ((hieu ve) OR (hieu van)) cham soc va hanh tai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te ((sach v) OR (sach 2)) nang ma hoi. ((hieu ve) OR (hieu van)) cham soc va hanh tai cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te ((sach v) or (sach 2)) nang ma hoi. ((hieu ve) OR (hieu van)) cham soc va hanh tai cua tre".
• Adding a wildcard symbol may retrieve word variants: te ((sach v) or (sach 2)) nang ma hoi. ((hieu ve) OR (hieu van)) cham soc va hanh tai cua tre*.