Perhaps you should try some spelling variations:
tu tieng » luc tieng, tu tuong, tu trong
van hanh » van thanh, ban hanh, van anh
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
hieu va » lieu va, hieu qua
va nang » van nang, da nang, cam nang
vu nang » vuc nang, vu dang, v nang
co luc » coc luc, co luy
x hoi » xa hoi, o hoi, x ho
va co » vo co

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) OR (va nang)) x hoi. hieu 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) OR (va nang)) x hoi. hieu 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) OR (va nang)) x hoi. hieu va co luc van hanh ve ((su hien) or (tu tieng))".
• Adding a wildcard symbol may retrieve word variants: te sach ((vu nang) OR (va nang)) x hoi. hieu va co luc van hanh ve ((su hien) or (tu tieng))*.