Perhaps you should try some spelling variations:
thieu nien » thien nhien
nien cac » vien cac, dien cac, bien cac
toc tuan » ngoc tuan, quoc tuan, toc thai
su triet » su viet, su tien, ve triet
su sach » so sach, vu sach
tu nang » tru nang, tu nano, tu lang
tu nong » tu dong, tu cong, tu tong
cac toc » cac toi, cac nuoc, cac thoi
anh vi » hanh vi, anh va, anh ve
vi su » va su, ve su, ki su

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 ((tu nang) or (tu nong)) xa hoi. thieu nien cac toc tuan anh vi su triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ((tu nang) OR (tu nong)) xa hoi. thieu nien cac toc tuan anh vi su triet.
• Adding a wildcard symbol may retrieve word variants: su sach ((tu nang) or (tu nong)) xa hoi. thieu nien cac toc tuan anh vi su triet*.