Perhaps you should try some spelling variations:
van hanh » van thanh, ban hanh, van anh
su sach » so sach, vu sach
vu nang » vuc nang, va nang, vu dang
hieu va » lieu va, hieu qua
su viet » so viet
v nang » va nang, van nang, voi nang
va cam » va cham, va cac, va cao
vi su » va su, ve su, ki su
tuan » quan, tran, luan

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

• Performing a fuzzy search may retrieve terms with similar spellings: su sach ((v nang) OR (vu nang)) xa hoi. hieu va cam xuc ((van hanh) or (tuan anh)) vi su viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ((v nang) OR (vu nang)) xa hoi. hieu va cam xuc ((van hanh) OR (tuan anh)) vi su viet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ((v nang) OR (vu nang)) xa hoi. hieu va cam xuc ((van hanh) or (tuan anh)) vi su viet".
• Adding a wildcard symbol may retrieve word variants: su sach ((v nang) OR (vu nang)) xa hoi. hieu va cam xuc ((van hanh) or (tuan anh)) vi su viet*.