Perhaps you should try some spelling variations:
su triet » su viet, su tien, ve triet
luoc van » luoc can, luoc va, luot van
va trien » va truyen, va thiet, va tuyen
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
luc van » luu van, duc van, luc va
va nhan » van nhan, ca nhan, va phan
hieu va » lieu va, hieu qua
anh vi » hanh vi, anh va, anh ve
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: tu sach ky nang x hoi. hieu va nhan ((luc van) OR (luoc van)) anh vi ((va trien) or (su triet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky nang x hoi. hieu va nhan ((luc van) OR (luoc van)) anh vi ((va trien) OR (su triet)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ky nang x hoi. hieu va nhan ((luc van) OR (luoc van)) anh vi ((va trien) or (su triet))".
• Adding a wildcard symbol may retrieve word variants: tu sach ky nang x hoi. hieu va nhan ((luc van) OR (luoc van)) anh vi ((va trien) or (su triet))*.