Perhaps you should try some spelling variations:
hieu viec » nhieu viec, hieu ve, sieu viet
viec cac » vien cac, viec cua, viec lam
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
cao hoa » cao hoat, cao khoa, cau hoa
va hang » van hang, va nang, va lang
hang vi » hang va, hanh vi, hang di
cua tre » cua te, cua triet, dua tren
cuu tre » cau tren, cau treo
cac tu » cac thu, cach tu, cac du

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 ky nang cao hoa. hieu viec cac tu va hang vi ((cua tre) OR (cuu tre))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ky nang cao hoa. hieu viec cac tu va hang vi ((cua tre) OR (cuu tre))".
• Adding a wildcard symbol may retrieve word variants: tu sach ky nang cao hoa. hieu viec cac tu va hang vi ((cua tre) OR (cuu tre))*.