Perhaps you should try some spelling variations:
su triet » su viet, su tien, ve triet
vien dai » hien dai
ban hanh » ban hang
van hanh » van thanh, van anh, van ban
vien cac » vien bach, vien da, gian cac
su sach » so sach, vu sach
sach ky » sac ky, sach y, sach ty
lang xa » lang ha, dang xay, lang van
ky lang » ky nang, ky dang, ky tang
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 ky lang xa hoi. hieu ((vien cac) OR (vien dai)) nuoc ((van hanh) or (ban hanh)) vi su triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ky lang xa hoi. hieu ((vien cac) OR (vien dai)) nuoc ((van hanh) OR (ban hanh)) vi su triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ky lang xa hoi. hieu ((vien cac) OR (vien dai)) nuoc ((van hanh) or (ban hanh)) vi su triet".
• Adding a wildcard symbol may retrieve word variants: su sach ky lang xa hoi. hieu ((vien cac) OR (vien dai)) nuoc ((van hanh) or (ban hanh)) vi su triet*.