Perhaps you should try some spelling variations:
su triet » su viet, su tien, ve triet
sanh thi » anh thi, oanh thi, nhanh thi
dan lanh » dan canh, dan hanh, dat lanh
thuc dan » thuc hanh, hoc dan, thuc vat
hoang xa » hoang ha, hoang va, hoang xuan
so sanh » do sanh
hang xa » hang va, hang ca, lang xa
va cam » va cham, va cac, va cao
dao su » dao suu, dan su, cao su
ve cam » ve cham, ve cac, ve cai

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

• Performing a fuzzy search may retrieve terms with similar spellings: so sanh thi ((hang xa) or (hoang xa)) hoi. hieu ((ve cam) OR (va cam)) thuc dan lanh dao su triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so sanh thi ((hang xa) OR (hoang xa)) hoi. hieu ((ve cam) OR (va cam)) thuc dan lanh dao su triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "so sanh thi ((hang xa) or (hoang xa)) hoi. hieu ((ve cam) OR (va cam)) thuc dan lanh dao su triet".
• Adding a wildcard symbol may retrieve word variants: so sanh thi ((hang xa) or (hoang xa)) hoi. hieu ((ve cam) OR (va cam)) thuc dan lanh dao su triet*.