Perhaps you should try some spelling variations:
ve triet » va trien, su triet
pham duy » pham duc
hanh dao » lanh dao, thanh dat, thanh dam
sach thu » sach thue, sach thieu, sach tham
duy tuan » duy luan, duy tan, quy tuan
han tai » hang tai, nhan tai, van tai
sach ty » sach y, sach tu, xach tay
hieu ve » hieu va, hieu van
ve pham » vi pham, v pham, ve phan
x hoi » xa hoi, o hoi, x ho

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 ty) or (sach thu)) nang x hoi. hieu ve pham duy tuan ((hanh dao) or (han tai)) ve triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach ty) OR (sach thu)) nang x hoi. hieu ve pham duy tuan ((hanh dao) OR (han tai)) ve triet.
• Adding a wildcard symbol may retrieve word variants: tu ((sach ty) or (sach thu)) nang x hoi. hieu ve pham duy tuan ((hanh dao) or (han tai)) ve triet*.