Perhaps you should try some spelling variations:
thuoc sach » hoc sach, nuoc sach, thuat sach
dang xay » dang van, van xay
nhan luc » nang luc
dau tren » dau tien, dat tren, dau tieng
lang xa » lang ha, lang van
va hanh » van hanh, va thanh, va danh
hanh va » hang va, hanh vi
ca tren » cau tren, cu tren, la tren
va nhan » van nhan, ca nhan, va phan
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: thuoc sach y ((lang xa) or (dang xay)) hoi. lieu va nhan luc va hanh va ((ca tren) or (dau tren))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thuoc sach y ((lang xa) OR (dang xay)) hoi. lieu va nhan luc va hanh va ((ca tren) OR (dau tren)).
• Adding a wildcard symbol may retrieve word variants: thuoc sach y ((lang xa) or (dang xay)) hoi. lieu va nhan luc va hanh va ((ca tren) or (dau tren))*.