Perhaps you should try some spelling variations:
thuat sach » thuat lanh, thuat san
van thanh » ban thanh, van tuan
hieu viec » nhieu viec, hieu ve, sieu viet
vien can » vien canh, vien cac, vien cao
sach ly » sach y, sach lo, sach ty
vien ca » vien cac, vien cao, vien da
ly nang » ky nang, ly hang, ly vang
cac lo » cac lop, cac bo, cac ho
cac co » cac cong

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

• If you are trying to use Boolean operators, they must be ALL CAPS: thuat sach ly nang x ho. hieu viec ((cac lo) OR (cac co)) van thanh ((vien ca) OR (vien can)) viet~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thuat sach ly nang x ho. hieu viec ((cac lo) or (cac co)) van thanh ((vien ca) OR (vien can)) viet~".
• Adding a wildcard symbol may retrieve word variants: thuat sach ly nang x ho. hieu viec ((cac lo) or (cac co)) van thanh ((vien ca) OR (vien can)) viet*.