Perhaps you should try some spelling variations:
nhieu viec » hieu viec, nhien viet
trinh tu » trinh ky, trinh do
trinh te » trinh he, trinh ke, trinh le
tu sach » thu sach, te sach, tu cach
cua luc » cua duc, cua tuc, cua cuc
nang ma » tang ma, sang ma, nang cao
su sach » so sach, vu sach
cua tre » cua te, cuu tre, cua triet
ma hoi » mai hoi, xa hoi, ma hoa
luc va » duc va, tuc va, loc 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 (su sach)) ky nang ma hoi. nhieu viec cua luc va ((trinh te) OR (trinh tu)) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (su sach)) ky nang ma hoi. nhieu viec cua luc va ((trinh te) OR (trinh tu)) cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) or (su sach)) ky nang ma hoi. nhieu viec cua luc va ((trinh te) OR (trinh tu)) cua tre".
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (su sach)) ky nang ma hoi. nhieu viec cua luc va ((trinh te) OR (trinh tu)) cua tre*.