Perhaps you should try some spelling variations:
su triet » su viet, su tien, ve triet
va thanh » gia thanh, ban thanh, va tinh
vu sach » vu bach, su sach, vu khach
sach ky » sac ky, sach y, sach ty
va danh » va dinh, va dan, va hanh
va cam » va cham, va cac, va cai
va cao » va cac, va co, va dao
ki su » ky su

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: vu sach ky nang x ho. hieu ((va cam) OR (va cao)) tu ((va thanh) or (va danh)) ki su triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: vu sach ky nang x ho. hieu ((va cam) OR (va cao)) tu ((va thanh) OR (va danh)) ki su triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "vu sach ky nang x ho. hieu ((va cam) OR (va cao)) tu ((va thanh) or (va danh)) ki su triet".
• Adding a wildcard symbol may retrieve word variants: vu sach ky nang x ho. hieu ((va cam) OR (va cao)) tu ((va thanh) or (va danh)) ki su triet*.