Perhaps you should try some spelling variations:
dau tieng » dau tien, cau tieng, day tieng
thu sach » tu sach, thuat sach, thuoc sach
sach ty » sach y, sach tu, sach thu
ty nang » ky nang, ty xang, ty hang
nang xa » nang x, lang xa, nang ma
va danh » va dinh, va dan, dia danh
va hanh » van hanh, va thanh, ban hanh
va nam » van nam, ha nam
va nay » va ngay, va cay
vi dau » vi dai, va dau, bi dau

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

• Performing a fuzzy search may retrieve terms with similar spellings: thu sach ty nang xa hoi. hieu ((va nam) OR (va nay)) thuoc ((va danh) or (va hanh)) vi dau tieng~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach ty nang xa hoi. hieu ((va nam) OR (va nay)) thuoc ((va danh) OR (va hanh)) vi dau tieng.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach ty nang xa hoi. hieu ((va nam) OR (va nay)) thuoc ((va danh) or (va hanh)) vi dau tieng".
• Adding a wildcard symbol may retrieve word variants: thu sach ty nang xa hoi. hieu ((va nam) OR (va nay)) thuoc ((va danh) or (va hanh)) vi dau tieng*.