Perhaps you should try some spelling variations:
sach thi » sach thu, sach tai, sach thieu
thi nang » thi cong, ki nang, thi hanh
tinh van » trinh van, dinh van, tinh va
te sach » toc sach
luu tre » luu tru, cuu tre
va tinh » may tinh
cao luc » bao luc, cao duc, cao suc
hieu va » lieu va, hieu qua
luy tre » luyen tre
va cao » va cac, va co, va dao
luc va » duc va, tuc va, loc va
x hoi » xa hoi, o hoi, 5 hoi

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

• Performing a fuzzy search may retrieve terms with similar spellings: te sach thi nang ((x hoi) or (x ho)). hieu va cao luc va tinh van ((luu tre) or (luy tre))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach thi nang ((x hoi) OR (x ho)). hieu va cao luc va tinh van ((luu tre) OR (luy tre)).
• Adding a wildcard symbol may retrieve word variants: te sach thi nang ((x hoi) or (x ho)). hieu va cao luc va tinh van ((luu tre) or (luy tre))*.