Perhaps you should try some spelling variations:
su triet » su viet, su tien, ve triet
ban hanh » ban hang
nhan luc » nang luc
luc ban » duc ban, cuc ban, luc bat
va nhan » van nhan, ca nhan, va phan
tu sach » thu sach, su sach, te sach
ty hang » ly hang, ty xang, thi hang
ty nang » ky nang, ty xang, ly nang
hieu va » lieu va, hieu qua

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) OR (ty hang)) xa hoi. hieu va nhan luc ban hanh vi ((va thiet) or (su triet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ((ty nang) OR (ty hang)) xa hoi. hieu va nhan luc ban hanh vi ((va thiet) OR (su triet))*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ((ty nang) OR (ty hang)) xa hoi. hieu va nhan luc ban hanh vi ((va thiet) or (su triet))*".