Perhaps you should try some spelling variations:
vien cay » vien cac, vien xay, vien can
vien cao » vien cac, vien dai, vien da
thuc van » thuc vat, thuc dan, thuc va
van hanh » van thanh, ban hanh, van anh
vu sach » vu bach, su sach, vu khach
sach ty » sach y, sach tu, sach thu
ty nang » ky nang, ty xang, ty hang
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 nang xa hoi. hieu ((vien cay) OR (vien cao)) thuc van hanh vi cua tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "vu sach ty nang xa hoi. hieu ((vien cay) OR (vien cao)) thuc van hanh vi cua tre".
• Adding a wildcard symbol may retrieve word variants: vu sach ty nang xa hoi. hieu ((vien cay) OR (vien cao)) thuc van hanh vi cua tre*.