Perhaps you should try some spelling variations:
van hanh » van thanh, ban hanh, van anh
cau tren » cu tren, dau tren, ca tren
tu sach » thu sach, su sach, te sach
sach ty » sach y, sach tu, sach thu
nang xa » lang xa, nang ma, mang xa
hieu va » lieu va, hieu qua
va cham » va chat, va tham
soc van » hoc van, oc van, sac van
vi cau » va cau, ve cau, di cau

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: tu sach ty ((nang xa) or (nang x)) hoi. hieu va cham soc van hanh vi cau tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ty ((nang xa) OR (nang x)) hoi. hieu va cham soc van hanh vi cau tren.
• Adding a wildcard symbol may retrieve word variants: tu sach ty ((nang xa) or (nang x)) hoi. hieu va cham soc van hanh vi cau tren*.