Perhaps you should try some spelling variations:
tu tieng » luc tieng, tu tuong, tu trong
van hanh » van thanh, ban hanh, van anh
sach vu » sach va, sach tu, sach uu
su hien » su kien, su tien, thu hien
hanh ve » hanh vi, hanh va, hanh kem
luc van » luoc van, luu van, duc van
te sach » toc sach
vu nang » vuc nang, va nang, vu dang
hieu va » hieu qua
co luc » coc luc, co luy
x hoi » xa hoi, o hoi, x ho

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

• Performing a fuzzy search may retrieve terms with similar spellings: te sach vu nang x hoi. ((hieu va) OR (lieu va)) co luc van hanh ve ((su hien) or (tu tieng))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach vu nang x hoi. ((hieu va) OR (lieu va)) co luc van hanh ve ((su hien) OR (tu tieng)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach vu nang x hoi. ((hieu va) OR (lieu va)) co luc van hanh ve ((su hien) or (tu tieng))".
• Adding a wildcard symbol may retrieve word variants: te sach vu nang x hoi. ((hieu va) OR (lieu va)) co luc van hanh ve ((su hien) or (tu tieng))*.