Perhaps you should try some spelling variations:
vien cay » vien cac, vien cao, vien xay
van hanh » van thanh, ban hanh, van anh
thuc van » thuc vat, thuc dan, thuc va
vien dai » hien dai
sach ty » sach tu, sach thu, xach tay
nang xa » nang x, lang xa, nang ma
cua tre » cua te, cuu tre, cua triet
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: vu ((sach ty) OR (sach y)) nang xa hoi. hieu ((vien cay) or (vien dai)) thuc van hanh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: vu ((sach ty) OR (sach y)) nang xa hoi. hieu ((vien cay) OR (vien dai)) thuc van hanh vi cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "vu ((sach ty) OR (sach y)) nang xa hoi. hieu ((vien cay) or (vien dai)) thuc van hanh vi cua tre".
• Adding a wildcard symbol may retrieve word variants: vu ((sach ty) OR (sach y)) nang xa hoi. hieu ((vien cay) or (vien dai)) thuc van hanh vi cua tre*.