Perhaps you should try some spelling variations:
su triet » su viet, su tien, ve triet
va thanh » gia thanh, ban thanh, va tinh
xa thanh » ha thanh, ta thanh, gia thanh
su sach » so sach
hieu ve » hieu va, hieu van
vu sach » vu bach, vu khach
cac tac » cac toc, cac bac, cac dac
ve cac » va cac, vien cac
x hoi » xa hoi, o hoi, x ho
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) or (vu sach)) ky nang x hoi. hieu ve cac tac ((xa thanh) OR (va thanh)) vi su triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((su sach) OR (vu sach)) ky nang x hoi. hieu ve cac tac ((xa thanh) OR (va thanh)) vi su triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((su sach) or (vu sach)) ky nang x hoi. hieu ve cac tac ((xa thanh) OR (va thanh)) vi su triet".
• Adding a wildcard symbol may retrieve word variants: ((su sach) or (vu sach)) ky nang x hoi. hieu ve cac tac ((xa thanh) OR (va thanh)) vi su triet*.