Perhaps you should try some spelling variations:
hieu cao » chieu cao, hieu cac, hieu ca
chat luc » chat xuc, chat lua, nhan luc
va trien » va truyen, va tuyen, va tieng
hanh lam » thanh lap, hanh kem, hanh va
van hanh » van thanh, ban hanh, van anh
hoang xa » hoang ha, hoang va, hoang xuan
luc van » luoc van, luu van, duc van
su sach » so sach, vu sach
sach ty » sach y, sach tu, sach thu
hang xa » hang va, hang ca, lang xa
thiet » thieu

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 ((hang xa) or (hoang xa)) hoi. hieu cao chat luc van hanh lam ((va trien) OR (va thiet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ty ((hang xa) OR (hoang xa)) hoi. hieu cao chat luc van hanh lam ((va trien) OR (va thiet)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ty ((hang xa) or (hoang xa)) hoi. hieu cao chat luc van hanh lam ((va trien) OR (va thiet))".
• Adding a wildcard symbol may retrieve word variants: su sach ty ((hang xa) or (hoang xa)) hoi. hieu cao chat luc van hanh lam ((va trien) OR (va thiet))*.