Perhaps you should try some spelling variations:
hieu viec » nhieu viec, hieu ve, sieu viet
thu sach » thuat sach, thuoc sach, thu hoach
danh vai » danh sai, danh va, doanh van
tu sach » su sach, te sach, tu cach
cac lop » cac hop, cac loai
vai cua » dai cua, hai cua, lai cua
va danh » va dinh, va dan, va hanh
cua tre » cua te, cuu tre, cua triet
nang xa » nang x, lang xa, nang ma
cac lo » cac co, cac bo, cac ho

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)) ky nang xa hoi. hieu viec ((cac lo) or (cac lop)) va danh vai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (thu sach)) ky nang xa hoi. hieu viec ((cac lo) OR (cac lop)) va danh vai cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) OR (thu sach)) ky nang xa hoi. hieu viec ((cac lo) or (cac lop)) va danh vai cua tre".
• Adding a wildcard symbol may retrieve word variants: ((tu sach) OR (thu sach)) ky nang xa hoi. hieu viec ((cac lo) or (cac lop)) va danh vai cua tre*.