Perhaps you should try some spelling variations:
thanh do » thanh pho, thanh hoa, thanh loi
thu sach » thuat sach, thuoc sach, thu hoach
nang cau » nang cao, hang cau, nang dau
thanh de » hanh de, thanh ve, thanh le
tu sach » su sach, te sach, tu cach
cuu tre » cua tre, cau tren, cau treo
hieu ve » hieu va, hieu van
y nang » ky nang, ly nang, v nang
ve cac » va cac, vien cac
du va » dau va, tu va, su va

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((tu sach) OR (thu sach)) y nang cau hoi. hieu ve cac du va ((thanh de) or (thanh do)) cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (thu sach)) y nang cau hoi. hieu ve cac du va ((thanh de) OR (thanh do)) cuu tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) OR (thu sach)) y nang cau hoi. hieu ve cac du va ((thanh de) or (thanh do)) cuu tre".
• Adding a wildcard symbol may retrieve word variants: ((tu sach) OR (thu sach)) y nang cau hoi. hieu ve cac du va ((thanh de) or (thanh do)) cuu tre*.