Perhaps you should try some spelling variations:
va trien » va truyen, va thiet, va tuyen
va triet » va thiet, ve triet, cua triet
hanh lam » thanh lap, hanh kem, hanh va
van hanh » van thanh, ban hanh, van anh
hieu cao » chieu cao, hieu cac, hieu ca
chat luc » chat xuc, chat lua, nhan luc
hang xa » hoang xa, hang va, hang ca
ty hang » ly hang, ty xang, thi hang
luc van » luoc van, luu van, duc van
vu sach » vu bach, vu khach
su sach » so sach

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) or (vu sach)) ty hang xa hoi. hieu cao chat luc van hanh lam ((va triet) OR (va trien))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((su sach) OR (vu sach)) ty hang xa hoi. hieu cao chat luc van hanh lam ((va triet) OR (va trien)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((su sach) or (vu sach)) ty hang xa hoi. hieu cao chat luc van hanh lam ((va triet) OR (va trien))".
• Adding a wildcard symbol may retrieve word variants: ((su sach) or (vu sach)) ty hang xa hoi. hieu cao chat luc van hanh lam ((va triet) OR (va trien))*.