Perhaps you should try some spelling variations:
su sach » so sach
va hanh » van hanh, va thanh, va danh
thuc va » thuc vat, thuc dan, thuc day
cua tre » cua te, cuu tre, cua triet
tang ma » mang may, tang van
vu sach » vu bach, vu khach
ma hoi » mai hoi, xa hoi, ma hoa
va cam » va cham, va cac, va cao
y tang » ky tang, 6 tang, 7 tang
vi cua » vai cua, di cua
ve cam » ve cham, ve cac, ve cai

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) OR (vu sach)) y tang ma hoi. hieu ((ve cam) or (va cam)) thuc va hanh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((su sach) OR (vu sach)) y tang ma hoi. hieu ((ve cam) OR (va cam)) thuc va hanh vi cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((su sach) OR (vu sach)) y tang ma hoi. hieu ((ve cam) or (va cam)) thuc va hanh vi cua tre".
• Adding a wildcard symbol may retrieve word variants: ((su sach) OR (vu sach)) y tang ma hoi. hieu ((ve cam) or (va cam)) thuc va hanh vi cua tre*.