Perhaps you should try some spelling variations:
su triet » su viet, su tien, ve triet
sach thu » sach thue, sach thieu, sach tham
thu nang » thi nang, thu hang, thu bang
hoang ki » hoang kim, hoang kinh, hoang thi
thuc van » thuc vat, thuc dan, thuc va
tuc van » truc van, tuc va, duc van
su sach » so sach, vu sach
nang xa » nang x, lang xa, nang ma
ve cam » ve cham, ve cac, ve cai
va cam » va cham, va cac, va cao
ki su » ky su

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 thu nang xa hoi. hieu ((ve cam) or (va cam)) ((tuc van) OR (thuc van)) hoang ki su triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach thu nang xa hoi. hieu ((ve cam) OR (va cam)) ((tuc van) OR (thuc van)) hoang ki su triet*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach thu nang xa hoi. hieu ((ve cam) or (va cam)) ((tuc van) OR (thuc van)) hoang ki su triet*".