Perhaps you should try some spelling variations:
dau tren » dau tien, dat tren, dau tieng
van hanh » van thanh, ban hanh, van anh
van pham » san pham, van phan, van phat
hieu van » hieu va, thien van, lieu va
hanh ve » hanh vi, hanh va, hanh kem
duc van » duc va, duc tan, duc manh
ky lang » ky nang, ky dang, ky tang
te sach » toc sach
lang xa » lang ha, dang xay, lang van
ve dau » va dau, ve du, ke dau

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((((tu cach) or (tu cac))) or (te sach)) ky lang xa hoi. hieu van pham duc van hanh ve dau tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((((tu cach) OR (tu cac))) OR (te sach)) ky lang xa hoi. hieu van pham duc van hanh ve dau tren.
• Adding a wildcard symbol may retrieve word variants: ((((tu cach) or (tu cac))) or (te sach)) ky lang xa hoi. hieu van pham duc van hanh ve dau tren*.