Perhaps you should try some spelling variations:
va thanh » ban thanh, va tinh, le thanh
tang mai » tang ma, tang tai, lang mai
nhan luc » nang luc
su sach » so sach, vu sach
lai cua » dai cua, hai cua, lai chau
vai cua » dai cua, hai cua, bai cua
sach ty » sach y, sach tu, sach thu
va nhan » van nhan, ca nhan, va phan
hieu va » lieu va, hieu qua
mai hoi » mai khoi, dai hoi, lai hoi
ty tang » tay tang, ty xang, ty hang

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

• Performing a fuzzy search may retrieve terms with similar spellings: su sach ty tang mai hoi. hieu va nhan luc ((va thanh) OR (gia thanh)) ((vai cua) or (lai cua)) tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ty tang mai hoi. hieu va nhan luc ((va thanh) OR (gia thanh)) ((vai cua) OR (lai cua)) tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ty tang mai hoi. hieu va nhan luc ((va thanh) OR (gia thanh)) ((vai cua) or (lai cua)) tre".
• Adding a wildcard symbol may retrieve word variants: su sach ty tang mai hoi. hieu va nhan luc ((va thanh) OR (gia thanh)) ((vai cua) or (lai cua)) tre*.