Perhaps you should try some spelling variations:
cam truc » cau truc, nam truc, lam truoc
nang mai » nang tai, lang mai, nang cai
va hanh » van hanh, va thanh, va danh
truc va » thuc va, thuc vat, trung va
qua cam » qua cham, qua cac, qua ca
nang ma » tang ma, sang ma, nang cao
cua tre » cua te, cuu tre, cua triet
sach v » sach va, sach 2, sach vay
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 y)) ((nang mai) OR (nang ma)) hoi. hieu qua cam truc va hanh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te ((sach v) OR (sach y)) ((nang mai) OR (nang ma)) hoi. hieu qua cam truc va hanh vi cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te ((sach v) or (sach y)) ((nang mai) OR (nang ma)) hoi. hieu qua cam truc va hanh vi cua tre".
• Adding a wildcard symbol may retrieve word variants: te ((sach v) or (sach y)) ((nang mai) OR (nang ma)) hoi. hieu qua cam truc va hanh vi cua tre*.