Perhaps you should try some spelling variations:
va trien » va truyen, va thiet, va tuyen
va triet » va thiet, ve triet, cua triet
hieu van » hieu va, thien van, lieu va
cau phuc » cau truc, chau phu, huu phuc
nang mai » nang ma, nang tai, lang mai
mai hoi » mai khoi, dai hoi, lai hoi
van cau » van dau, van hau, van chat
phuc va » phuc vu, thuc va, chuc va
va danh » va dinh, va dan, va hanh
danh vi » hanh vi, dinh vi, danh di
co sach » bo sach, cuon sach, hoc sach
so sach » so sanh, bo sach, hoc sach
y nang » ky nang, ly nang, v nang

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((so sach) or (co sach)) y nang mai hoi. hieu van cau phuc va danh vi ((va triet) or (va trien))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((so sach) OR (co sach)) y nang mai hoi. hieu van cau phuc va danh vi ((va triet) OR (va trien)).
• Adding a wildcard symbol may retrieve word variants: ((so sach) or (co sach)) y nang mai hoi. hieu van cau phuc va danh vi ((va triet) or (va trien))*.