Perhaps you should try some spelling variations:
sach thi » sach thu, sach tai, sach thieu
thi hanh » thi thanh
van hanh » van thanh, ban hanh, van anh
tu sach » thu sach, su sach, te sach
hanh xa » hanh va, hanh ma, hanh xu
hieu ve » hieu va, hieu van
cau luc » cau truc, cau phuc
luc van » luoc van, luu van, duc van
kiem va » kien va, kiem tra, nhiem va
ve cau » ke cau, va cau, ve cac
kem va » kiem van
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: tu sach thi hanh xa hoi. hieu ve cau luc van hanh ((kem va) or (kiem va)) thiet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach thi hanh xa hoi. hieu ve cau luc van hanh ((kem va) OR (kiem va)) thiet.
• Adding a wildcard symbol may retrieve word variants: tu sach thi hanh xa hoi. hieu ve cau luc van hanh ((kem va) or (kiem va)) thiet*.