Perhaps you should try some spelling variations:
hanh doi » thanh doi, hanh noi, hang doi
su viet » so viet
luu van » cuu van, luan van, luu hanh
xay hoi » xa hoi, tay hoi, cay phoi
hieu va » lieu va, hieu qua
luc van » luoc van, duc van, luc va
doi su » oi su, don su, voi su
san ky » sang ky, van ky, ban ky
dan ky » van ky
va cam » va cham, va cac, va cao

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu ((san ky) or (dan ky)) van xay hoi. hieu va cam ((luc van) OR (luu van)) hanh doi su viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((san ky) OR (dan ky)) van xay hoi. hieu va cam ((luc van) OR (luu van)) hanh doi su viet*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu ((san ky) or (dan ky)) van xay hoi. hieu va cam ((luc van) OR (luu van)) hanh doi su viet*".