Perhaps you should try some spelling variations:
vanh dai » van dai, vanh tai, lanh dao
dua tren » dung tren
su triet » su viet, su tien, ve triet
cua viet » ca viet, hoa viet, cua vat
su sach » so sach, vu sach
hieu ve » hieu va, hieu van
ve pham » vi pham, v pham, ve phan
va vanh » va van, va danh, va hanh
y nang » ky nang, ly nang, v nang
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: su sach y nang x hoi. hieu ve pham duc va vanh dai ((dua tren) or (((su triet) or (cua viet))))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach y nang x hoi. hieu ve pham duc va vanh dai ((dua tren) OR (((su triet) OR (cua viet)))).
• Adding a wildcard symbol may retrieve word variants: su sach y nang x hoi. hieu ve pham duc va vanh dai ((dua tren) or (((su triet) or (cua viet))))*.