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

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) OR (ve 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) OR (ve triet)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ((tu nang) or (tu nong)) xa hoi. thieu nien cac toc tuan anh vi ((su triet) OR (ve 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) OR (ve triet))*.