Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
hanh lai » hanh lam, hanh tai, thanh lap
van hanh » van thanh, ban hanh, van anh
pham duy » pham duc
van pham » san pham, van phan, van phat
duy van » duy vat, dung van
tu sach » thu sach, su sach, te sach
ty nang » ky nang, ty xang, ty hang
sach ty » sach y, sach tu, sach thu
ca viet » va viet, co viet, hoa viet
lai ca » lai cua, lai cam, loai ca
o hoi » co hoi, o hoc, o hai
x hoi » x ho, 5 hoi

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 ((((x hoi) OR (xa hoi))) or (o hoi)). hieu van pham duy van hanh lai ca viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ty nang ((((x hoi) OR (xa hoi))) OR (o hoi)). hieu van pham duy van hanh lai ca viet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ty nang ((((x hoi) OR (xa hoi))) or (o hoi)). hieu van pham duy van hanh lai ca viet".
• Adding a wildcard symbol may retrieve word variants: tu sach ty nang ((((x hoi) OR (xa hoi))) or (o hoi)). hieu van pham duy van hanh lai ca viet*.